What is the purpose of a ballast tank on an oil tanker?

Navigating through narrow channels

What is the purpose of a venting system on an oil tanker?

Allowing the escape of gases and vapors

What is the function of a cargo heating system on an oil tanker?

Maintaining the temperature of the cargo

Parts of an Oil Tanker

Science Exam Parts of the Atom: The atom consists of a nucleus at its center, containing protons (positively charged) and neutrons (neutral), while electrons (negatively charged) orbit in electron shells around the nucleus. Atomic Number: The atomic number of an element is the number of protons in its nucleus. It defines the element and determines its place on the periodic table. Properties of Metals: Metals have properties like conductivity, malleability (can be flattened into sheets), and ductility (can be drawn into wires). Elements, Compounds, and Mixtures: Elements consist of only one type of atom. Compounds are made of two or more different elements chemically bonded. Mixtures are combinations of substances that are physically mixed but not chemically bonded. Homogeneous and Heterogeneous Mixtures: Homogeneous mixtures have a uniform composition (e.g., saltwater), while heterogeneous mixtures have different phases (e.g., oil and water). Changes of State: Changes like melting, evaporation, and condensation are examples of physical changes of state. Chemical and Physical Properties: Chemical properties describe how a substance can change to form a new substance, while physical properties are characteristics like color, texture, and state (solid, liquid, gas). Physical and Chemical Change: A physical change involves the appearance or state of matter, but the substance remains the same. A chemical change involves the formation of new substances. Chemical Equations: Chemical reactions can be represented with chemical equations that show reactants (what you start with) and products (what is formed). Chemical Formulas: Chemical formulas represent the composition of compounds. For example, NaHCO3 is sodium bicarbonate, consisting of one sodium (Na), one hydrogen (H), one carbon (C), and three oxygen (O) atoms. Energy: Types of Energy: Energy can be kinetic (related to motion), potential (stored energy), thermal (heat energy), electrical, chemical, and more. Units of Energy: Common units of energy include joules (J) and calories (cal). Law of Conservation of Energy: Energy cannot be created or destroyed, only transferred or transformed from one form to another. Energy Transfer and Transformation: Energy moves from one object to another, changing forms along the way. Useful and Waste Energy: Useful energy is what can be harnessed and used for a specific purpose. Waste energy is energy that is not used and is often lost. Energy Flow Diagrams: These diagrams show how energy is transferred or transformed within a system. Energy Efficiency: Efficiency is a measure of how much useful energy is obtained from a system. It can be calculated using the equation: Efficiency = (Useful Energy Output / Total Energy Input) x 100%. Fossil Fuels and Renewable Energy: Fossil fuels, like coal, oil, and natural gas, are non-renewable sources of energy. Renewable energy sources include solar, wind, and hydroelectric power. Variables: Independent Variable: The variable that is manipulated or changed in an experiment. Dependent Variable: The variable that is measured or observed and is affected by changes in the independent variable. Controlled Variables: Factors that are kept constant to ensure a fair and accurate experiment.

Camshaft: A rotating shaft in an engine that controls the opening and closing of the intake and exhaust valves. Aftercooler (air to air): A device that cools the compressed air from a turbocharger using outside air. Glow Plugs: Heating elements used to aid in starting diesel engines in cold temperatures. Timing Cover: The cover that protects the timing gears and belt or chain in an engine. Exhaust Manifold: A component that collects exhaust gases from multiple cylinders and directs them to the exhaust pipe. Oil Suction Tube: A tube that draws oil from the oil pan to the oil pump. Air Compressor: A device that increases the pressure of air and is often used to power air brakes or pneumatic tools. Oil Cooler: A device that cools the engine oil, helping prevent it from overheating. Supercharger/Blower: A device that increases the pressure of the air-fuel mixture entering the engine to boost power. Piston Rings: Rings around the piston that seal the combustion chamber, control oil consumption, and conduct heat. Crankshaft: A shaft that converts the linear motion of the pistons into rotational motion to power the vehicle. Oil Pan: A reservoir at the bottom of the engine that collects and holds the engine oil. Connecting Rod: Connects the piston to the crankshaft, converting the piston's motion into rotational motion. Stroke: The distance the piston travels within the cylinder, from top dead center to bottom dead center. 2 Cycle: A type of engine that completes a power cycle in two strokes of the piston. Crankshaft Main Bearing: The bearing that supports the crankshaft in the engine block. Aftercooler (water/coolant): A device that cools the compressed air from a turbocharger using water or coolant. Water Pump: A pump that circulates coolant through the engine and radiator to prevent overheating. Oil Filter: A filter that removes contaminants from the engine oil. Vibration Dampener: A device attached to the crankshaft to reduce engine vibrations. Piston Wrist Pin: The pin that connects the piston to the connecting rod. Valve Cover: The cover that protects the engine's valves and camshaft. Cylinder Block: The main structure of an engine that houses the cylinders and other components. ECM/ECU: Electronic Control Module or Electronic Control Unit, which controls various engine functions. Cylinder Head: The top part of the cylinder that contains the combustion chamber, valves, and spark plugs. Oil Pump: A pump that circulates oil through the engine to lubricate moving parts. Cylinder Liner: A sleeve inside the cylinder that protects it from wear and corrosion. TDC (Top Dead Center): The highest position the piston reaches in its stroke. Bore: The diameter of a cylinder in an engine. Flywheel: A heavy wheel that stores rotational energy to smooth out engine operation. Crankshaft Rod Bearing: The bearing that connects the crankshaft to the connecting rod. Push Tube / Push Rod: Rods that transmit motion from the camshaft to the valves. Piston: A cylindrical component that moves up and down within the cylinder to create power. Flywheel Housing: The casing that surrounds and supports the flywheel. Valve Lifter or Cam Follower: A component that follows the camshaft lobes to open and close the valves. Turbo: A device that increases the engine’s power by forcing more air into the combustion chamber. Intake & Exhaust Valves: Valves that control the intake of air and the exhaust of gases in the engine. Intake Manifold: A manifold that distributes the air-fuel mixture or air to the cylinders. Rocker Arm: A lever that transfers camshaft motion to the valves. Wastegate: A valve that controls the exhaust gases flowing to the turbocharger, preventing excessive boost pressure. Fuel Injector: A device that sprays fuel into the combustion chamber. Fuel Pump: A pump that moves fuel from the fuel tank to the engine. BDC (Bottom Dead Center): The lowest position the piston reaches in its stroke. 4 Cycle: A type of engine that completes a power cycle in four strokes (intake, compression, power, exhaust). Articulated Piston: A piston with two pieces (crown and skirt) joined by a pivot, allowing some flexibility in movement.

Agriculture Agriculture is the main source of livelihood in every country in the region except Brunei and Singapore. Agricultural employment, however, has been declining. More than two-thirds of the workforces of Cambodia and Laos practice agriculture. As the economies of the ASEAN countries have been restructured toward growth in industry and services, there has been a corresponding decline in the proportion of the gross domestic product (GDP) derived from agriculture, most significantly in Indonesia, Malaysia, and Thailand. Agricultural output in Southeast Asia has increased significantly since 1970. There are wide variations in this growth across the region, with the greatest gains in Malaysia and Thailand and little or no increase in Cambodia, Laos, and Vietnam. Hunger and malnutrition are problems in pockets of even the most developed countries, but they have been especially serious in Cambodia because of crop failures and internal strife. The condition of the rural population everywhere is clearly related to limited access to land, the landless experiencing greater poverty and poorer health. Landlessness is perhaps most serious in the Philippines. The dominant form of agriculture in the region is wet-rice cultivation. Where conditions permit, two crops typically are planted each year. Other food crops such as corn (maize), cassava, and pulses (legumes) frequently are grown in drier areas where there is too little water for a second planting of rice. Rice production requires a reliable water supply. Thailand and the Philippines rely heavily on rain-fed systems, while Indonesia utilizes irrigation to a large extent. Irrigation or some other form of water control is especially critical in the cultivation of the high-yielding varieties (HYVs) of rice that have been introduced since the 1960s. The spread of the so-called Green Revolution—in which HYVs and chemical fertilizers and pesticides are utilized—has brought mixed results. There is little doubt that production has increased because of the higher yields of these hybrid strains and because their more rapid maturation increases the possibility of multiple annual crops. Frequently, however, poorer farmers are not able to take advantage of these strains, because of the high cost of their use. The goal of rice self-sufficiency has been difficult to achieve for most countries. A large variety of cash crops are grown for the local and export markets, both on large commercial estates and by individual growers or smallholders. Tree crops are the most important in terms of value, although the area devoted to them is limited largely to equatorial areas. Rubber and palm oil are significant in Malaysia, Indonesia, and southern Thailand, while coconuts and sugar are important in the Philippines. Other major export crops are cacao, coffee, and spices, while crops grown largely for local and regional consumption include chilies, sweet potatoes, peanuts (groundnuts), and tobacco. The cultivation of opium poppies is important in parts of Myanmar and Thailand. The emphasis on rubber and palm oil production is in response to a considerable (though fluctuating) worldwide demand for these commodities and because of a nearly continuous harvest period that provides year-round employment. Foreign corporations once dominated production, but, as the region’s countries gained independence, much of the production was nationalized. Government ownership continues to predominate, with increasing private ownership. Fishing contributes only a token amount to the GDP of Southeast Asian countries, but it is an important livelihood in certain areas and supplies a significant portion of the local diet. Marine output has gradually expanded with new technologies. The maritime nations of Thailand, Indonesia, Malaysia, and the Philippines all have globally important fishing industries. Shrimp catches are especially in demand in the world economy. Aquaculture has become increasingly important in the region, such species as shrimp, carp, and grouper being raised in excavated ponds.

Translator: Joseph Geni Reviewer: Morton Bast Before March, 2011, I was a photographic retoucher based in New York City. We're pale, gray creatures. We hide in dark, windowless rooms, and generally avoid sunlight. We make skinny models skinnier, perfect skin more perfect, and the impossible possible, and we get criticized in the press all the time, but some of us are actually talented artists with years of experience and a real appreciation for images and photography. On March 11, 2011, I watched from home, as the rest of the world did, as the tragic events unfolded in Japan. Soon after, an organization I volunteer with, All Hands Volunteers, were on the ground, within days, working as part of the response efforts. I, along with hundreds of other volunteers, knew we couldn't just sit at home, so I decided to join them for three weeks. On May the 13th, I made my way to the town of Ōfunato. It's a small fishing town in Iwate Prefecture, about 50,000 people, one of the first that was hit by the wave. The waters here have been recorded at reaching over 24 meters in height, and traveled over two miles inland. As you can imagine, the town had been devastated. We pulled debris from canals and ditches. We cleaned schools. We de-mudded and gutted homes ready for renovation and rehabilitation. We cleared tons and tons of stinking, rotting fish carcasses from the local fish processing plant. We got dirty, and we loved it. For weeks, all the volunteers and locals alike had been finding similar things. They'd been finding photos and photo albums and cameras and SD cards. And everyone was doing the same. They were collecting them up, and handing them in to various places around the different towns for safekeeping. Now, it wasn't until this point that I realized that these photos were such a huge part of the personal loss these people had felt. As they had run from the wave, and for their lives, absolutely everything they had, everything had to be left behind. At the end of my first week there, I found myself helping out in an evacuation center in the town. I was helping clean the onsen, the communal onsen, the huge giant bathtubs. This happened to also be a place in the town where the evacuation center was collecting the photos. This is where people were handing them in, and I was honored that day that they actually trusted me to help them start hand-cleaning them. Now, it was emotional and it was inspiring, and I've always heard about thinking outside the box, but it wasn't until I had actually gotten outside of my box that something happened. As I looked through the photos, there were some were over a hundred years old, some still in the envelope from the processing lab, I couldn't help but think as a retoucher that I could fix that tear and mend that scratch, and I knew hundreds of people who could do the same. So that evening, I just reached out on Facebook and asked a few of them, and by morning the response had been so overwhelming and so positive, I knew we had to give it a go. So we started retouching photos. This was the very first. Not terribly damaged, but where the water had caused that discoloration on the girl's face had to be repaired with such accuracy and delicacy. Otherwise, that little girl isn't going to look like that little girl anymore, and surely that's as tragic as having the photo damaged. (Applause) Over time, more photos came in, thankfully, and more retouchers were needed, and so I reached out again on Facebook and LinkedIn, and within five days, 80 people wanted to help from 12 different countries. Within two weeks, I had 150 people wanting to join in. Within Japan, by July, we'd branched out to the neighboring town of Rikuzentakata, further north to a town called Yamada. Once a week, we would set up our scanning equipment in the temporary photo libraries that had been set up, where people were reclaiming their photos. The older ladies sometimes hadn't seen a scanner before, but within 10 minutes of them finding their lost photo, they could give it to us, have it scanned, uploaded to a cloud server, it would be downloaded by a gaijin, a stranger, somewhere on the other side of the globe, and it'd start being fixed. The time it took, however, to get it back is a completely different story, and it depended obviously on the damage involved. It could take an hour. It could take weeks. It could take months. The kimono in this shot pretty much had to be hand-drawn, or pieced together, picking out the remaining parts of color and detail that the water hadn't damaged. It was very time-consuming. Now, all these photos had been damaged by water, submerged in salt water, covered in bacteria, in sewage, sometimes even in oil, all of which over time is going to continue to damage them, so hand-cleaning them was a huge part of the project. We couldn't retouch the photo unless it was cleaned, dry and reclaimed. Now, we were lucky with our hand-cleaning. We had an amazing local woman who guided us. It's very easy to do more damage to those damaged photos. As my team leader Wynne once said, it's like doing a tattoo on someone. You don't get a chance to mess it up. The lady who brought us these photos was lucky, as far as the photos go. She had started hand-cleaning them herself and stopped when she realized she was doing more damage. She also had duplicates. Areas like her husband and her face, which otherwise would have been completely impossible to fix, we could just put them together in one good photo, and remake the whole photo. When she collected the photos from us, she shared a bit of her story with us. Her photos were found by her husband's colleagues at a local fire department in the debris a long way from where the home had once stood, and they'd recognized him. The day of the tsunami, he'd actually been in charge of making sure the tsunami gates were closed. He had to go towards the water as the sirens sounded. Her two little boys, not so little anymore, but her two boys were both at school, separate schools. One of them got caught up in the water. It took her a week to find them all again and find out that they had all survived. The day I gave her the photos also happened to be her youngest son's 14th birthday. For her, despite all of this, those photos were the perfect gift back to him, something he could look at again, something he remembered from before that wasn't still scarred from that day in March when absolutely everything else in his life had changed or been destroyed. After six months in Japan, 1,100 volunteers had passed through All Hands, hundreds of whom had helped us hand-clean over 135,000 photographs, the large majority — (Applause) — a large majority of which did actually find their home again, importantly. Over five hundred volunteers around the globe helped us get 90 families hundreds of photographs back, fully restored and retouched. During this time, we hadn't really spent more than about a thousand dollars in equipment and materials, most of which was printer inks. We take photos constantly. A photo is a reminder of someone or something, a place, a relationship, a loved one. They're our memory-keepers and our histories, the last thing we would grab and the first thing you'd go back to look for. That's all this project was about, about restoring those little bits of humanity, giving someone that connection back. When a photo like this can be returned to someone like this, it makes a huge difference in the lives of the person receiving it. The project's also made a big difference in the lives of the retouchers. For some of them, it's given them a connection to something bigger, giving something back, using their talents on something other than skinny models and perfect skin. I would like to conclude by reading an email I got from one of them, Cindy, the day I finally got back from Japan after six months. "As I worked, I couldn't help but think about the individuals and the stories represented in the images. One in particular, a photo of women of all ages, from grandmother to little girl, gathered around a baby, struck a chord, because a similar photo from my family, my grandmother and mother, myself, and newborn daughter, hangs on our wall. Across the globe, throughout the ages, our basic needs are just the same, aren't they?" Thank you. (Applause) (Applause)

“On this night, we share a roof protecting us from fleets of inequity. Our unification promises a better tomorrow. Those larger than myself, sitting on their marble thrones, sipping blood from cups composed of human skin and singing songs of so-called virtue, grow weaker each moment. Their caravans are revolting. There is hope yet. There is progress! Though tonight may mark a countdown, it is still a celebration. Look at all we have done, not just for Trials but for Palatium Infra as a whole. In four years, when I’m no longer Sovereignty, the Spoiled Purity and his people will continue to strive. So drink! Smoke! Crush up those exotic plants and snort them! We will not falter, weaken, or wane. Our influence is expanding, and somebody new opens their eyes every day. Even the Silbys of Aculeus have reached alarming potentials despite their embittered minds. So long as you relish in tonight, dance, and pray to your “dead” Gods, our revolution shall rise beyond the bounds of class, and when I’m only a commoner, we shall rise again beyond our brainwashed adversaries! Cheers, my people. Cheers!” Followers raised their cups. Some clinked theirs together. Others stood still and screamed breathlessly in agreement. I smiled with courtesy, then stepped off my platform. My voice still rang across the cellar. Speeches before were grander. Those displays were supposed to be emptying, and yet this one left me bloated, swollen tight. I watched as they popped the corks of their bottles and chanted in the name of Purity. Maybe the quality of my words wasn’t what mattered to them anyway, so long as I screamed loud enough. There’s no merit in attacking your people, a voice corrected me. “That’s right,” I said aloud. “Knox, my-my Sovereign!” squealed a nearby devotee, jittering as he stuffed his face with catered pastries. He was one I’d never seen before or had failed to remember. “Look what I’ve found! It’s wine, and not the shoddy Infran kind, either. Earth-made with good fruit! I don’t know how anyone managed to get their hands on this. Maybe some space travel mischief.” He giggled and held up a small glass bottle. “How neat.” “I want you to have it, Sir.” I nodded my head. “Yes, of course. Thank you.” Backing off into the midst of rowdy disciples, I clutched the bottle. What a waste of grapes. It could have been jam instead. Earthly food had a superior taste, ripe with delicate intricacies and nostalgia, but Palatium Infra had mastered the art of alcohol. Why waste your time with a drunkenness so sad and sickening? The booze of trash. Not many more followers approached me. The barren peroration must have upset them. My hands itched to submerge into my suit pockets, and my legs stood suddenly numb, wobbling. Four more years until I’m nothing. But tonight, you are nothing. “Shut up,” I told myself. Tightly packed together in the corner of the dwelling sat the Sibyls. A mound of writhing fabric and tones of skin made up their unified silhouette. I snapped the strap of the nearest gown, balancing on my hands and knees, waving the bottle before them. In their almost rodent nature, narrow noses prodded my way. Their dresses wrinkled and fell to their ankles. Knees dropped, and eyes widened. Many grumbled at me like hungry she-beasts. Those newer ones with faded curtains for hair, sunken eyes, and dirtied nails looked, hid their face, then sobbed. I imagined them in a pack together, fighting wildly against the Spoiled Purity in their rat decorum–biting down with square teeth laced with rabies. “I’ve got you all something,” I said. “Go back off to your pedestal and yap some more. We don’t want it.” A woman rose from the pile and spat. “You don’t even know what it is yet. It's Earth hooch, or more likely a near-flawless replica. I figured you girls would also like a chance to enjoy yourselves tonight.” “Your playmates have been harassing us since the moment you hung the banners and opened the cellar door.” The youngest, with a striking cyan mop upon her head, uncoiled from the mass. What was she now? 20, 21? We celebrated a birthday recently, I thought as she spun around me. “I remember something about a promise. Multiple promises, actually. Are you trying to bribe us into just shutting up and taking it? Because if another sticky, 40-year-old, Earth-born virgin gropes my shoulder, I’m going to have an aneurysm!” the girl continued. “Why not an Infran follower? Do you like it when they touch you?” I returned her accusing tone. “I’m sorry, sweet prophets, that you feel I’ve neglected my duties. I’ll keep a better eye out. Remember, you can always just holler if somebody is bothering you. And Anwen, friend, if I’ve ever tried to bribe you with anything, it was certainly the hair dye. I mean, look at you! Such handsomeness!” I exclaimed. The other Siblys began to encircle her, uttering compliments or even announcements of their envy. Anwen disappeared in a wink with flushed cheeks back into the mound. “I’ll just leave this here.” Smiling, I set down the bottle. ** “141, 143. . .” I counted each step as I trekked the staircase. There was no doubt I lost track somewhere. The ledges kept spawning under my feet, infinitely multiplying until I wasn’t moving at all–swallowing me up in a whirlpool of stone. My tie still hung around my neck, and my blazer remained tied around my hips as a skirt. Streaks of red dribbled off from the cavity in my chest. It was a gorgeous marking, sensual to my fingertips as I traced its edges. Purity, oh, Purity. Purity and his wings of burnt skin. Purity and his many faces. Purity the spoiled. Purity the mutilated. The Silbys did not bother waiting for me. On bare feet, they stormed up the stairs to their room. A trail of red, though in paint unlike mine, streamed after them. None looked remotely near me as they squeaked and gossiped intangibly. I saved them, those Infran broads, enlightened them. As much as they liked to deny it, spit at me, and bask in the thought of their victimhood, in this home, they stood empowered. You’ve done well, my thoughts affirmed, though in the manner of an insincere commentator rather than a hype man. Teeth grace in tile violin goes laundry paper when. It dissolved into an intruding drivel. I rubbed my head and sniveled. “Do you need help, Knox?” called a Silby. Fattened by my coddling, her shadow fell upon me from the doorway steps ahead. I attempted counting again. There must’ve been at least another hundred between me and her. “I’m hallucinating some,” I said, breathing deeply to suppress a burp as I struggled to recall her name. Two syllables. Typically Latin, though sometimes English. Drops of slobber leaked from my mouth. “I’m hallucinating some, Tybal. Do you like your name, Tybal? I would have named you something better. Ty-Tyballinia. No, we’d have to eliminate the ‘ball’ aspect. It sounds too crude.” “One foot in front of the other,” she said. So I walked. Mess greeted me at the doorway. Dirtied culinary obscured the dark wooden countertops, and the sink lay running. I approached the kitchen table, sat, and set my face down upon its cool wooden surface. Assaulting my nose was the smell of neglected flowers, like soil mixed with the kind of sweet cough medicine that would have left me gagging as a child. Open windows whispered songs of the twilight hour through the vessels of busy trolleys and shooting guns. My mouth strained to vomit, but there was nothing in my stomach to regurgitate except the petals of Stulto’s bloom, which came out effortlessly in little sputters. Teetering, I stood up and brushed disgorged plant parts off the tabletop. “Love,” I said as I slogged up yet another staircase. “Are you awake?” She said she’d wait. Somebody’s gotten her. No, she always misses movie night. That sleepyhead, I assured myself. There was a stirring amidst the manor’s cloak of dusk. Portraits of myself, my wife, and my daughter turned to face me as the hallway lights flickered, escaping their quartz frames to penetrate my ears with nonsense. The taxidermied heads of Infran creatures bared their teeth. I stopped to stare at my favorite, an adabactor with daunting spiked tusks poking out from its forehead. Its nose remained black and sharp, and its eyes wide with malice. “Where is my Spes, Adaba-boy? Is she sleepy?” There’s someone in the house. The sounds of the stirring rose along with my blood pressure. Footsteps orbited around me, drawing near and far and then near again, little dancers in the dark. The carpet immersed me in its mass of purples and blues, leaving my skin stained indigo and my vision abstracted. I toiled to reach the master bedroom across the aisle as it stretched out to me with bright lights and celestial howling, like a dove struggling in a pool of oil. Never again with Stulto’s bloom. Never again on what was already a bad night. My hand brushed the doorknob, and the high abruptly faded into only a persistent hum-buzz twirling around my brain. The portraits returned to their typical depression–Spes posing with her ax, Ari’s school photo, and myself in the cap I wore when addressing the military with the Verbis emblem embroidered in its center. All lifeless shots. Who were they for when they captured not the subject’s essence but only some fragment of their identity? They used to feel personal, not advertisements of some supposed characters. Servants, babysitters, and likewise civilian guests, I reminded myself, mustn’t forget whose home they’re in. Yet my body moved independently, taking Ari’s from its hook and laying it backward against the wall to hide her distant grin and tamed posture. It was time for new pictures. Sweet ones, real ones; time was ticking. I approached my own when the stirring began again. Groans and squeals erupted from the vents as if someone had set a pen of pigs loose in my crawlspace. No, not the crawlspace, my bedroom door. I turned the ruby knob. Underneath a blanket wrestled my two squealing piglets, their skins melting together beneath the layer of duvet. Fishnet leggings and manicured nails outstretched and scraped at the sheet beneath them. One raised its head, a salmon-colored man with sweat running down his forehead. Through the crack in the door, we met eyes, his Infran Dr. Sesuss nose flaring its narrow nostrils. No mark of the Spoiled Purity existed carved onto his naked body. My chest felt tight. I stepped back. I was suffocating. Spes emerged from the linens, her hair flowing down her back and her dark skin glistening in front of the bedroom window. She giggled and held the man, the blanket falling and revealing inches of her body I had not seen in months. “Darling,” whispered the rosy-faced man, “look.” He was unfathomably ugly and grotesquely young, with beady, lifeless pupils that dilated when he faced me. The excess flesh on his face sagged while he bit down on his thin lips. My wife faced me, gasped, and strained to cover herself. Suddenly, I was a stranger. A small child who had walked into his parents having sex. I unfurled the door completely. “Get out of my house,” I said. The man stayed in place. “Get out of my house,” I repeated. “Knox,” Spes began. Tears ran down her round cheeks. “Shut up!” I turned to the man, picking up a marble trophy from on top of my dresser. “Get out of my house! I’ll kill you!” “Knox!” Spes sobbed. “God damn it! I hate you! You barely look at me. Every day, there’s less passion. God, God, God, I don’t want to fuck a dead man!” she screamed, “You get out! Get! Get!” My hands wrapped tighter around the statue. That pig of a man was attached to her at the side, his face equipped with a scowl that challenged mine. He thought I was weak; frail like a decaying dementia-ridden senior. I imagined his skull bashed in, his scowl gone, and the feist and confidence in his face beaten into numbness. A new portrait was in order of such brutality, him as a splintered slab of wood, rashed and beaten, a carcass licking my boot. The churning in my brain had come back. Every wall shook. Clock faces came to life and rang in alarm. Indescribable noises caressed my eardrum before breaking into sorrowful weeps. Was it my own? I stared at Spes in motionless frenzy, clenched my teeth, and screamed like a siren. Passionless. What a lie! An excuse, more like. One that erased all my ventures, reducing me to a nobody. But I was not a nobody. I thought of my sect, my campaigns, my endurance through the political brutality of my empty hive-mind world–even my collection of literature, maps, and artifacts. I thought of daring nights alone with Spes when we were young, ravaging each other, two sardonic eggheads suddenly overcome with desire. The veins in my neck throbbed as I gasped for air. It was all I had. I threw the figurine at the man’s head. Eye shut, I heard the thud. A million singing voices of victory flooded out of the cracks in the floorboard. Proving myself a man to the woman I loved in a display of fervent violence was passion. I strained my ears for his cries, though I did not look yet. There had to be a pause, a moment of relief, where I stood tall as a skyscraper and seemingly fought to stay contained in front of my wife and her wounded, quivering paramour. Frantic footsteps rushed off the bed and past my side. I turned and grappled against myself to seize my wife’s shoulder. “Spes!” My eyelids lifted. Escaping was the man with that same numb expression in which I had imagined him. “You’re insane,” he said. I swiveled back towards the bed. With her curly locks flowing over her breasts and her limbs bent at her sides, Spes sat limp pressed against the headboard, her forehead bludgeoned and the statue resting on her stomach. Lips pursed and sweet, my Renaissance beauty reclined there in the guise of a squashed bug. But she was not dead. The desk ornament I flung was only the size of my shoe. Spes, that dramatist, may have been slightly hurt but was far from dead. She only wanted me to think she was to observe me at my most distraught, like a leech feeding on misery. “Get up.” Staggering toward the bed, I said. “You wanted passion? I showed you passion. ‘Shoved it right into your head. Of course, we both know who that gesture was meant for. . .” I fumbled to find my wit. Cold skin met my hands as I stroked her face, unable to resist checking her pulse, even though she was not dead. “I love you, Spes,” I said. Rain pelted against a nearby window. “Spes, please. Please.” No vibration answered my plea. I lifted my hand, sitting next to her now. Tears did not come. There was not any blood on the trophy, but when I picked it up, it felt to be now only a cruel instrument. It depicted a younger me in white marble, with my glasses and collared shirt being the only things painted. Both were in pink. It was a favorable color. I scrambled from the bed to vomit pure digestive bile on the rug. My stomach heaved. I ran my nails along every piece of myself I saw, a dog chasing my tail. As I slammed myself against walls and convulsed, my own heart grew ever louder in my chest. “Dad? I heard–” Ari’s slippered feet hammered across the floor. “Mom? Mom?” I kept my eyes on the storm. Silence fell. “She-She isn’t—your—.” Gasps interrupted every syllable she spoke. “You’re a murderer. Bad. Like they said,” she breathed, “ You beat her!” The words became mush, alphabet soup. Ari ran back down the hall. “My-My mom is dead. . . .Yes. . . Manor of the Trials Sovereignty. . .Ari Sorkin. . . I’m afraid he’s going to hurt me,” she said, presumably over the phone. It was all too fast. I crawled onto the windowsill, opened the glass, and let myself plummet into the alley below. Gusts of wind howled. The lack of motion or sensation informed me I had passed and again lived. Another Palatium Infra, another strange planet in which the celestial endowed rotting men with the opportunity to inhabit. Was this it? Was it all just an impossible limbo of galactic traveling? My surroundings were overwhelmingly gray, an abyss of clouds. Perhaps I had now met the real coming world, and my family and old friends lived here, ready to rush to my sides, lift me up, and jump for joy. Spes would be there. She would be enraged, but at least she’d be there. You are a bad man. You are a bad man. My eyelashes fluttered. There was a tugging sensation in my leg. The fog was wavering along with my ascendance. “No,” I yearned, trying to grip the clouds and stick them in place. “Stay with me.” But the peace was fleeting. I felt the cement under me and the moist garments clinging to my figure. My leg burned. Carefully, I craned my neck, only to observe the promenade as my surroundings. The most underwhelming of filth and danger, individually Infran. Forever my coming world. What a fool I was, having forgotten my blessing. Those idiot Gods could not tell the difference between assassination and self-infliction; a faulty insurance plan. The urge to cry at last set over me, and so I sat and wailed hot salvia into my palm, shielding my mouth to muffle the noise. Thunder echoed my hushed howling. Raindrops turned to pebbles. Under the ambiance of the stormy night, I could have sworn I heard troops stomping, guns cocking, and the chanting of my name. They had all been waiting for this. Billboards came to life, and I could only sit and spectate as the scenery flashed red. I inhaled fear and sobriety through runny nostrils. “Trials Sovereign Vsevolod “Knox” Sorkin is currently at large for the suspected homicide of Spes Sorkin, breaking the first term of the Sovereignty Charter. We now instruct you to report any sightings of the Earth-born, caucasian, roughly 195 centimeters tall, brown-haired, and brown-eyed man to your local Guard post. One can identify the suspected convict specifically by an occult tattoo of Purity’s Coronet on his lower back. No attempted execution or elongated punishment will take place until our Guards conduct an autopsy proving his guilt, per Life’s 1238 commandment. We cannot be sure when or if the Gods will revoke his blessing. Remember, when Gods frown upon strife, opt for a peaceful life. We permit all grieving festivities until Cagidus 4th. Good year!” towering buildings sang out in broadcast, repeating that same convoluted message quicker the instant it ended. Sometimes, the announcer spoke in Latin for the Infran children, other times in Chinese, Hindi, or Spanish to cater to those of irrelevant tongues. You aren’t a bad man. You are a stupid boy. Puddles sloshed. Somebody was approaching. I didn’t dare waste any remaining energy avoiding the Guards and their prodding blades. How did that phrase go? You dug your grave. Now lie in it. And so I embraced the cement. “Knox?” said the Guard. No, her tone was too sincere, and no authority would proceed in such a manner. There wasn’t confirmation on whether or not I was armed, and it wasn’t as if she could shoot me first. She was a partygoer, having just left from the cellar’s backdoor. I shooed her away with my hand. She hovered, and I discerned her shadow hesitating over my body. A man could not rot in peace. “Come on, get up! They’re after you!” Hands reached around my torso, struggling to handle my weight as they urged me onto my feet. That leg, the burning one, my right, trembled and bent unnaturally upon impact with the ground. The partygoer slung my arm over her shoulder, balancing me. My eyes caught a glimpse of a cyan mop. “Anwen?” I rasped, “hu-who let you out?” Keys jangled in her hands–my keys. “I escaped,” she said casually, coercing me to walk beside her. “Quicken your pace. I just heard somebody on your front porch. ‘You see that compost bin down the alley? We’re gonna burrow right down into the depth of that. If they open it and uncover us, I’ll be on top, and I can hide you and act like I’m just a homeless amica trying to take a nap.” With a tightening grip, she led me like livestock to the stinking crate. “I don’t understand, Anwen,” I said. “They’re going to torture and kill you, stupid. You know they’ve been wanting to, and you just handed the opportunity to them!” “I understand that.” It was becoming increasingly challenging to hide the fragility emerging in my voice. “You said you were escaping. Why stop and help your captor?” “What else could I do? Leave you there?” Attempts to shove my wounded body inside its mass of discarded fruits and vegetables began. She yanked down upon my head and submerged me in the fertilizer sea. The evidence grows indisputable, I thought as I stared at the abruptly humane Infran girl, diving in after me, that I belong here. “Damn me to hell! I’ve killed her! My love is dead!” an uncontrollable cry leaped from my mouth. “Shut up! Soon you’ll be, too, if you don’t quiet down.” The actual noise of the Guards darted past us: disorientated marching, guns clanking against each other, cluttered belts rattling, the Latin squawking. One paused to open the bin’s lid, though only rummaged through the surface layer of peat before carrying on. “What are they talking about? I struggle with my Latin,” I whispered. “The search, mainly.” Aggression remained firey in Anwen’s clenched jaw. Though she sat on top of me, there was a monumental distance between our rain-soaked forms. I curled up into a ball, ducked my head between my knees, and dreamt of Spes, ignoring the stench of spoiled food rising from every crevice of my dwelling. The next coming world was due to adopt me again as I forced sleep. I prayed for a canyon of fluffy haze, where I waltzed with pale memories but found nothing but the petrifying stillness of my mind. Killed and ran. Violent as a Guard just to prove a point and watch it backfire. Why would any heaven want to welcome me? I clung to the picture of Spes in my head like it was the last ember of an extinguished flame. “Did you mean to kill her?” Anwen interrogated. “Someone like you would immutably believe yes.” “And who is someone like me? You can’t even treat me like a person for a moment, can you?” grating drama decorated her words. “You know my opinions. I have not seen much of your or your breed’s faces besides that of cruelty and ignorance.” I retorted. “I just saved you! Does that make me cruel and ignorant?” “It makes you an idiot, which is another word for somebody ignorant.” “And why am I an idiot?” She asked. “Because you helping me does no good. Thank you anyhow. Now, do yourself a favor and scram.” As she bent her leg in anticipation, preparing to strike me on the forehead, I sensed an invisible withdrawal widening the gap between us. “You never answered my question,” Anwen took me by the end of my tattered tie suddenly and started her game of shepherd and sheep over again, pulling me back up to the crate’s exit. It appeared as a shining light at the end of a maze of rubbish and mold. “No. Of course not. Spes was my everything,” I sniffled. “I knew it. You couldn’t even bring yourself to hit us, let alone murder your wife. The girls and I always figured you were sensitive.” My heart rate quickened. Today was one of humbling and misery–one to pray a hail spike would fall from the sky as sharp as a needle, pierce into my eyelid, and lobotomize me. I wished I could have merely died or hit my head hard enough not to have to deal with it all. No, I wished I was Anwen with her snarky, careless glow and lack of depth in her eyes. As we emerged from the compost bin together, I fantasized about strangling her until her face turned purple, her weakening spirit no longer categorizing me as “sensitive”, but the thought could only remind me of wielding that trophy and the microscopic traces of my wife’s tender skin tainting it, which turned my guts inside out. “That’s why I think you could use a little help,” Anwen said, “It seems like you can’t walk, either. Your leg is all twisted up.” She undid one of her trim pigtails and handed me the band. “Take off your tie and put up your hair. ‘Will make you less recognizable. Then swallow your pride and stick with me.”

1 .Sand soil • Has course/ large particles • they are larger than those of clay • Loses water quickly • Has less organic matter • Has good aeration • Allows good root penetration • Leaching of nutrients is more in sand soil. • Does not stick when wet 2. Clay soil • Has very fine particles which are closely packed • The soil is sticky when wet and can be moulded into any shape • It holds more water than sand and loam • It has poor drainage • It cracks when dry • It has poor aeration • It does not allow good root penetration 2 .Loam soil • Is a mixture of sand and clay particles • It half clay half sand • It can be easily moulded into a shape but easily crumbles • Holds water for a longer time than sand • It sticks on the hands when wet • It has good drainage • It has good aeration • It allows good root penetration • Loam is the best soil Soil Fertility • When soil has enough plant nutrients it is fertile • Soil fertility is the presence of nutrients in the soil • A farmer can add nutrients to the soil to make it fertile • This is done by applying fertilizers and compost. • A fertiliser is a substance that is added to the soil to increase fertility • Nutrients found in the soil include Nitrogen, Phosphorus and Potassium ( NPK ) • They are called major nutrients or macro nutrients because they are needed in large quantities Minor nutrients • Minor nutrients are needed in smaller quantities • Minor nutrients are also called micro nutrients or trace elements • Examples of minor nutrients are boron, iron, zinc, manganese, magnesium and molybdenum Soil erosion • Is the washing away of top soil by agents such as Water Wind Animals Humans 1. Water: • Water washes away soil when it rains. • Loose soil is washed away into dams and rivers. • Steep slopes also lead to soil erosion. • Ploughing 2 . Wind • The blowing away of soil by wind causes soil erosion. • When people cut down trees wind erosion easily takes place. • Type of soil also leads to wind erosion. Which soil type is easily eroded by wind? 3 . Animals • Animal cause soil erosion by overgrazing. • Overgrazing is when animals eat plant or vegetation leaving the ground surface bare. • Animals walking on the same pathway for a long time make the soil loose. • Animals that live underground also burrow loosening the soil. • This makes soil break easily and get washed away. WATER WATER CONSERVATION Water • Water is important in agriculture • It is used to: Clean farm tools Mould bricks Wash milking equipment Cool machines Provide homes(habitat) for fish Give animals drinking and bathing water Sources of Water Natural sources 1. Natural rains: • rain water from the clouds is a primary source of water. • It is used to water crops such as maize, millet, sorghum and so on during the rainy season. • Rain water that collects into the rivers and dams is used by animals and people for drinking. 2 . Rivers : • Rivers are some of the major sources of water for different activities such as fishing, boat cruising and irrigation. 3 . Streams : • A stream is a small river. • Streams supply water for irrigating garden crops especially in rural areas. • They are also a source of water for animals to drink and bath. Sources of Water 4 . Springs : • Springs are usually found on hilly areas. • They result from pressure of underground streams. • The pressure forces water underground to form a channel to the surface of the soil and flow above the ground. Sources of Water Man made sources Man discovered that water for agriculture was not enough during the rain and cool dry seasons. They decided to make structures which would harvest or collect and store water for future use. 1.Protected well: • Wells are dug in the ground by hand. • They are often lined with bricks and concrete so that they do not cave in. • Protected wells are covered, therefore are safe to drink from. 2 . borehole : • They are deep holes made by drilling machines. • Drilling can be done up to 70 metres deep. • Water is pumped using an electric pump or hand pump. Sources of Water 3 . Dams : • A dam is a large wall or barrier built to hold water to save it for future use. 4 . Weir : • A weir is made by construction a cement brick wall or concrete wall across a river to trap water and eroded soil. • water flows over the wall when the river is inflood. 5 .Water tank : • Is a temporary manmade water source. • Water from a water tank is usually harvested from roof tops or it works along a borehole or protected well as temporary storage. • Water is pumped from the borehole or protected well into the water tank. 6 . reservoir : • A large natural or manmade lake used as a source of water. PLANTS Uses of plants • Fibre for making clothes • Oil for cooking, making paint and chemicals • Sugar for tea • Wood for timber • Refreshing drinks and alcohol • Food for people and animals • Protect the soil from erosion • Plants supply us with fresh oxygen for breathing. • Some plant parts are used as medicine.

“There’s No Such Thing as Sound Science” by By Christie Aschwanden was a lead science writer for FiveThirtyEight. FiveThirtyEight, Science, Dec. 6, 2017 Science is being turned against itself. For decades, its twin ideals of transparency and rigor have been weaponized by those who disagree with results produced by the scientific method. Under the Trump administration, that fight has ramped up again. In a move ostensibly meant to reduce conflicts of interest, Environmental Protection Agency Administrator Scott Pruitt has removed a number of scientists from advisory panels and replaced some of them with representatives from industries that the agency regulates. Like many in the Trump administration, Pruitt has also cast doubt on the reliability of climate science. For instance, in an interview with CNBC, Pruitt said that “measuring with precision human activity on the climate is something very challenging to do.” Similarly, Trump’s pick to head NASA, an agency that oversees a large portion the nation’s climate research, has insisted that research into human influence on climate lacks certainty, and he falsely claimed that “global temperatures stopped rising 10 years ago.” Kathleen Hartnett White, Trump’s nominee to head the White House Council on Environmental Quality, said in a Senate hearing last month that she thinks we “need to have more precise explanations of the human role and the natural role” in climate change. The same entreaties crop up again and again: We need to root out conflicts. We need more precise evidence. What makes these arguments so powerful is that they sound quite similar to the points raised by proponents of a very different call for change that’s coming from within science. This other movement strives to produce more robust, reproducible findings. Despite having dissimilar goals, the two forces espouse principles that look surprisingly alike: Science needs to be transparent. Results and methods should be openly shared so that outside researchers can independently reproduce and validate them. The methods used to collect and analyze data should be rigorous and clear, and conclusions must be supported by evidence. These are the arguments underlying an “open science” reform movement that was created, in part, as a response to a “reproducibility crisis” that has struck some fields of science.1 But they’re also used as talking points by politicians who are working to make it more difficult for the EPA and other federal agencies to use science in their regulatory decision-making, under the guise of basing policy on “sound science.” Science’s virtues are being wielded against it. What distinguishes the two calls for transparency is intent: Whereas the “open science” movement aims to make science more reliable, reproducible and robust, proponents of “sound science” have historically worked to amplify uncertainty, create doubt and undermine scientific discoveries that threaten their interests. “Our criticisms are founded in a confidence in science,” said Steven Goodman, co-director of the Meta-Research Innovation Center at Stanford and a proponent of open science. “That’s a fundamental difference — we’re critiquing science to make it better. Others are critiquing it to devalue the approach itself.” Calls to base public policy on “sound science” seem unassailable if you don’t know the term’s history. The phrase was adopted by the tobacco industry in the 1990s to counteract mounting evidence linking secondhand smoke to cancer. A 1992 Environmental Protection Agency report identified secondhand smoke as a human carcinogen, and Philip Morris responded by launching an initiative to promote what it called “sound science.” In an internal memo, Philip Morris vice president of corporate affairs Ellen Merlo wrote that the program was designed to “discredit the EPA report,” “prevent states and cities, as well as businesses from passing smoking bans” and “proactively” pass legislation to help their cause. The sound science tactic exploits a fundamental feature of the scientific process: Science does not produce absolute certainty. Contrary to how it’s sometimes represented to the public, science is not a magic wand that turns everything it touches to truth. Instead, it’s a process of uncertainty reduction, much like a game of 20 Questions. Any given study can rarely answer more than one question at a time, and each study usually raises a bunch of new questions in the process of answering old ones. “Science is a process rather than an answer,” said psychologist Alison Ledgerwood of the University of California, Davis. Every answer is provisional and subject to change in the face of new evidence. It’s not entirely correct to say that “this study proves this fact,” Ledgerwood said. “We should be talking instead about how science increases or decreases our confidence in something.” The tobacco industry’s brilliant tactic was to turn this baked-in uncertainty against the scientific enterprise itself. While insisting that they merely wanted to ensure that public policy was based on sound science, tobacco companies defined the term in a way that ensured that no science could ever be sound enough. The only sound science was certain science, which is an impossible standard to achieve. “Doubt is our product,” wrote one employee of the Brown & Williamson tobacco company in a 1969 internal memo. The note went on to say that doubt “is the best means of competing with the ‘body of fact’” and “establishing a controversy.” These strategies for undermining inconvenient science were so effective that they’ve served as a sort of playbook for industry interests ever since, said Stanford University science historian Robert Proctor. The sound science push is no longer just Philip Morris sowing doubt about the links between cigarettes and cancer. It’s also a 1998 action plan by the American Petroleum Institute, Chevron and Exxon Mobil to “install uncertainty” about the link between greenhouse gas emissions and climate change. It’s industry-funded groups’ late-1990s effort to question the science the EPA was using to set fine-particle-pollution air-quality standards that the industry didn’t want. And then there was the more recent effort by Dow Chemical to insist on more scientific certainty before banning a pesticide that the EPA’s scientists had deemed risky to children. Now comes a move by the Trump administration’s EPA to repeal a 2015 rule on wetlands protection by disregarding particular studies. (To name just a few examples.) Doubt merchants aren’t pushing for knowledge, they’re practicing what Proctor has dubbed “agnogenesis” — the intentional manufacture of ignorance. This ignorance isn’t simply the absence of knowing something; it’s a lack of comprehension deliberately created by agents who don’t want you to know, Proctor said.2 In the hands of doubt-makers, transparency becomes a rhetorical move. “It’s really difficult as a scientist or policy maker to make a stand against transparency and openness, because well, who would be against it?” said Karen Levy, researcher on information science at Cornell University. But at the same time, “you can couch everything in the language of transparency and it becomes a powerful weapon.” For instance, when the EPA was preparing to set new limits on particulate pollution in the 1990s, industry groups pushed back against the research and demanded access to primary data (including records that researchers had promised participants would remain confidential) and a reanalysis of the evidence. Their calls succeeded and a new analysis was performed. The reanalysis essentially confirmed the original conclusions, but the process of conducting it delayed the implementation of regulations and cost researchers time and money. Delay is a time-tested strategy. “Gridlock is the greatest friend a global warming skeptic has,” said Marc Morano, a prominent critic of global warming research and the executive director of ClimateDepot.com, in the documentary “Merchants of Doubt” (based on the book by the same name). Morano’s site is a project of the Committee for a Constructive Tomorrow, which has received funding from the oil and gas industry. “We’re the negative force. We’re just trying to stop stuff.” Some of these ploys are getting a fresh boost from Congress. The Data Quality Act (also known as the Information Quality Act) was reportedly written by an industry lobbyist and quietly passed as part of an appropriations bill in 2000. The rule mandates that federal agencies ensure the “quality, objectivity, utility, and integrity of information” that they disseminate, though it does little to define what these terms mean. The law also provides a mechanism for citizens and groups to challenge information that they deem inaccurate, including science that they disagree with. “It was passed in this very quiet way with no explicit debate about it — that should tell you a lot about the real goals,” Levy said. But what’s most telling about the Data Quality Act is how it’s been used, Levy said. A 2004 Washington Post analysis found that in the 20 months following its implementation, the act was repeatedly used by industry groups to push back against proposed regulations and bog down the decision-making process. Instead of deploying transparency as a fundamental principle that applies to all science, these interests have used transparency as a weapon to attack very particular findings that they would like to eradicate. Now Congress is considering another way to legislate how science is used. The Honest Act, a bill sponsored by Rep. Lamar Smith of Texas,3 is another example of what Levy calls a “Trojan horse” law that uses the language of transparency as a cover to achieve other political goals. Smith’s legislation would severely limit the kind of evidence the EPA could use for decision-making. Only studies whose raw data and computer codes were publicly available would be allowed for consideration. That might sound perfectly reasonable, and in many cases it is, Goodman said. But sometimes there are good reasons why researchers can’t conform to these rules, like when the data contains confidential or sensitive medical information.4 Critics, which include more than a dozen scientific organizations, argue that, in practice, the rules would prevent many studies from being considered in EPA reviews.5 It might seem like an easy task to sort good science from bad, but in reality it’s not so simple. “There’s a misplaced idea that we can definitively distinguish the good from the not-good science, but it’s all a matter of degree,” said Brian Nosek, executive director of the Center for Open Science. “There is no perfect study.” Requiring regulators to wait until they have (nonexistent) perfect evidence is essentially “a way of saying, ‘We don’t want to use evidence for our decision-making,’” Nosek said. Most scientific controversies aren’t about science at all, and once the sides are drawn, more data is unlikely to bring opponents into agreement. Michael Carolan, who researches the sociology of technology and scientific knowledge at Colorado State University, wrote in a 2008 paper about why objective knowledge is not enough to resolve environmental controversies. “While these controversies may appear on the surface to rest on disputed questions of fact, beneath often reside differing positions of value; values that can give shape to differing understandings of what ‘the facts’ are.” What’s needed in these cases isn’t more or better science, but mechanisms to bring those hidden values to the forefront of the discussion so that they can be debated transparently. “As long as we continue down this unabashedly naive road about what science is, and what it is capable of doing, we will continue to fail to reach any sort of meaningful consensus on these matters,” Carolan writes. The dispute over tobacco was never about the science of cigarettes’ link to cancer. It was about whether companies have the right to sell dangerous products and, if so, what obligations they have to the consumers who purchased them. Similarly, the debate over climate change isn’t about whether our planet is heating, but about how much responsibility each country and person bears for stopping it. While researching her book “Merchants of Doubt,” science historian Naomi Oreskes found that some of the same people who were defending the tobacco industry as scientific experts were also receiving industry money to deny the role of human activity in global warming. What these issues had in common, she realized, was that they all involved the need for government action. “None of this is about the science. All of this is a political debate about the role of government,” she said in the documentary. These controversies are really about values, not scientific facts, and acknowledging that would allow us to have more truthful and productive debates. What would that look like in practice? Instead of cherry-picking evidence to support a particular view (and insisting that the science points to a desired action), the various sides could lay out the values they are using to assess the evidence. For instance, in Europe, many decisions are guided by the precautionary principle — a system that values caution in the face of uncertainty and says that when the risks are unclear, it should be up to industries to show that their products and processes are not harmful, rather than requiring the government to prove that they are harmful before they can be regulated. By contrast, U.S. agencies tend to wait for strong evidence of harm before issuing regulations. Both approaches have critics, but the difference between them comes down to priorities: Is it better to exercise caution at the risk of burdening companies and perhaps the economy, or is it more important to avoid potential economic downsides even if it means that sometimes a harmful product or industrial process goes unregulated? In other words, under what circumstances do we agree to act on a risk? How certain do we need to be that the risk is real, and how many people would need to be at risk, and how costly is it to reduce that risk? Those are moral questions, not scientific ones, and openly discussing and identifying these kinds of judgment calls would lead to a more honest debate. Science matters, and we need to do it as rigorously as possible. But science can’t tell us how risky is too risky to allow products like cigarettes or potentially harmful pesticides to be sold — those are value judgements that only humans can make.

A solution is a mixture in which one or more substances are uniformly distributed in another substance. Solutions can be mixtures of liquids, solids, or gases. For example, plasma, the liquid part of blood, is a very complex solution. It is composed of many types of ions and large molecules, as well as gases, that are dissolved in water. A solute (SAHL-YOOT) is a substance dissolved in the solvent. The particles that compose a solute may be ions, atoms, or molecules. The solvent is the substance in which the solute is dissolved. For example, when sugar, a solute, and water, a solvent, are mixed, a solution of sugar water results. Though the sugar dissolves in the water, neither the sugar molecules nor the water molecules are altered chemically. If the water is boiled away, the sugar molecules remain and are unchanged. Solutions can be composed of various proportions of a given solute in a given solvent. Thus, solutions can vary in concentra- tion. The concentration of a solution is the amount of solute dis- solved in a fixed amount of the solution. For example, a 2 percent saltwater solution contains 2 g of salt dissolved in enough water to make 100 mL of solution. The more solute dissolved, the greater is the concentration of the solution. A saturated solution is one in which no more solute can dissolve. Aqueous (AY-kwee-uhs) solutions—solutions in which water is the solvent—are universally important to living things. Marine microorganisms spend their lives immersed in the sea, an aqueous solution. Most nutrients that plants need are in aqueous solutions in moist soil. Body cells exist in an aqueous solution of intercellu- lar fluid and are themselves filled with fluid; in fact, most chemical reactions that occur in the body occur in aqueous solutions. Copyright © by Holt, Rinehart and Winston. All rights reserved. Liquid water Solid water Ice (solid water) is less dense than liquid water because of the structure of ice crystals. The water molecules in ice are bonded to each other in a way that creates large amounts of open space between the molecules, relative to liquid water. FIGURE 2-12 solvent from the Latin solvere, meaning “to loosen” Word Roots and Origins CHEMISTRY OF LIFE 43 ACIDS AND BASES One of the most important aspects of a living system is the degree of its acidity or alkalinity. What do we mean when we use the terms acid and base? Ionization of Water As water molecules move about, they bump into one another. Some of these collisions are strong enough to result in a chemical change: one water molecule loses a proton (a hydrogen nucleus), and the other gains this proton. This reaction really occurs in two steps. First, one molecule of water pulls apart another water molecule, or dissociates, into two ions of opposite charge: H2O ∏ H OH The OH ion is known as the hydroxide ion. The free H ion can react with another water molecule, as shown in the equation below. H H2O ∏ H3O The H3O ion is known as the hydronium ion. Acidity or alkalin- ity is a measure of the relative amounts of hydronium ions and hydroxide ions dissolved in a solution. If the number of hydronium ions in a solution equals the number of hydroxide ions, the solution is said to be neutral. Pure water contains equal numbers of hydro- nium ions and hydroxide ions and is therefore a neutral solution. Acids If the number of hydronium ions in a solution is greater than the number of hydroxide ions, the solution is an acid. For example, when hydrogen chloride gas, HCl, is dissolved in water, its mol- ecules dissociate to form hydrogen ions, H, and chloride ions, Cl, as is shown in the equation below. HCl ∏ H Cl These free hydrogen ions combine with water molecules to form hydronium ions, H3O. This aqueous solution contains many more hydronium ions than it does hydroxide ions, making it an acidic solution. Acids tend to have a sour taste; how- ever, never taste a substance to test it for acidity. In concentrated forms, they are highly corrosive to some materials, as you can see in Figure 2-13. Bases If sodium hydroxide, NaOH, a solid, is dissolved in water, it dissociates to form sodium ions, Na, and hydroxide ions, OH, as shown in the equation below. NaOH ∏ Na OH Copyright © by Holt, Rinehart and Winston. All rights reserved. Eco Connection onnection Acid Precipitation Acid precipitation, more commonly called acid rain, describes rain, snow, sleet, or fog that contains high levels of sulfuric and nitric acids. These acids form when sulfur dioxide gas, SO2, and nitrogen oxide gas, NO, react with water in the atmosphere to produce sulfuric acid, H2SO4, and nitric acid, HNO3. Acid precipitation makes soil and bodies of water, such as lakes, more acidic than normal. These high acid levels can harm plant and animal life directly. A high level of acid in a lake may kill mollusks, fish, and amphibians. Even in a lake that does not have a very elevated level of acid, acid precipitation may leach aluminum and magnesium from soils, poisoning water- dwelling species. Reducing fossil-fuel consump- tion, such as occurs in gasoline engines and coal-burning power plants, should reduce high acid levels in precipitation. Sulfur dioxide, SO2, which is produced when fossil fuels are burned, reacts with water in the atmosphere to produce acid precipitation. Acid precipitation, or acid rain, can make lakes and rivers too acidic to support life and can even corrode stone, such as the face of this statue. FIGURE 2-13 44 CHAPTER 2 This solution then contains more hydroxide ions than hydronium ions and is therefore defined as a base. The adjective alkaline refers to bases. Bases have a bitter taste; however, never taste a substance to test for alkalinity. They tend to feel slippery because the OH ions react with the oil on our skin to form a soap. In fact, commercial soap is the product of a reaction between a base and a fat. pH Scientists have developed a scale for comparing the relative con- centrations of hydronium ions and hydroxide ions in a solution. This scale is called the pH scale, and it ranges from 0 to 14, as shown in Figure 2-14. A solution with a pH of 0 is very acidic, a solution with a pH of 7 is neutral, and a solution with a pH of 14 is very basic. A solution’s pH is measured on a logarithmic scale. That is, the change of one pH unit reflects a 10-fold change in the acidity or alkalinity. For example, urine has 10 times the H3O ions at a pH of 6 than water does at a pH of 7. Vinegar, has 1,000 times more H3O ions at a pH of 3 than urine at a pH of 6, and 10,000 times more H3O ions than water at a pH of 7. The pH of a solution can be measured with litmus paper or with some other chemical indicator that changes color at various pH levels. Buffers The control of pH is important for living systems. Enzymes can function only within a very narrow pH range. The control of pH in organisms is often accomplished with buffers. Buffers are chemi- cal substances that neutralize small amounts of either an acid or a base added to a solution. As Figure 2-14 shows, the composition of your internal environment—in terms of acidity and alkalinity— varies greatly. Some of your body fluids, such as stomach acid and urine, are acidic. Others, such as intestinal fluid and blood, are

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