Count the number of morphemes in each word.

Count the number of words in a spoken sentence.

Count the number of objects. Choose the correct number symbol.

Figure 18-11 represents the amount of energy stored as organic material in each trophic level in an ecosystem. The pyramid shape of the diagram indicates the low percentage of energy transfer from one level to the next. On average, 10 percent of the total energy consumed in one trophic level is incor- porated into the organisms in the next. Why is the percentage of energy transfer so low? One reason is that some of the organisms in a trophic level escape being eaten. They eventually die and become food for decomposers, but the energy contained in their bodies does not pass to a higher trophic level. Even when an organism is eaten, some of the molecules in its body will be in a form that the consumer cannot break down and use. For example, a cougar cannot extract energy from the antlers, hooves, and hair of a deer. Also, the energy used by prey for cellu- lar respiration cannot be used by predators to synthesize new bio- mass. Finally, no transformation or transfer of energy is 100 percent efficient. Every time energy is transformed, such as during the reactions of metabolism, some energy is lost as heat. Limitations of Trophic Levels The low rate of energy transfer between trophic levels explains why ecosystems rarely contain more than a few trophic levels. Because only about 10 percent of the energy available at one trophic level is transferred to the next trophic level, there is not enough energy in the top trophic level to support more levels. Organisms at the lowest trophic level are usually much more abundant than organisms at the highest level. In Africa, for exam- ple, you will see about 1,000 zebras, gazelles, and other herbivores for every lion or leopard you see, and there are far more grasses and shrubs than there are herbivores. Higher trophic levels con- tain less energy, so, they can support fewer individuals.A population is a group of organisms that belong to the same species and live in a particular place at the same time. All of the bass living in a pond during a certain period of time make up a pop- ulation because they are isolated in the pond and do not interact with bass living in other ponds. The boundaries of a population may be imposed by a feature of the environment, such as a lake shore, or they can be arbitrarily chosen to simplify a study of the population. The humans shown in Figure 19-1 are part of the pop- ulation of a city. The properties of populations differ from those of individuals. An individual may be born, it may reproduce, or it may die. A population study focuses on a population as a whole—how many individuals are born, how many die, and so on. Population Size A population’s size is the number of individuals that the population contains. Size is a fundamental and important population property but can be difficult to measure directly. If a population is small and composed of immobile organisms, such as plants, its size can be determined simply by counting individuals. Often, though, individ- uals are too abundant, too widespread, or too mobile to be counted easily, and scientists must estimate the number of individuals in the population. Suppose that a scientist wants to know how many oak trees live in a 10 km2 patch of forest. Instead of searching the entire patch of forest and counting all the oak trees, the scientist could count the trees in a smaller section of the forest, such as a 1 km2 area. The scientist could then use this value to estimate the population of the larger area. SECTION 1 OBJECTIVES ● Describe the main properties that scientists measure when they study populations. ● Compare the three general patterns of population dispersion. ● Identify the measurements used to describe changing populations. ● Compare the three general types of survivorship curves. VOCABULARY population population density dispersion birth rate death rate life expectancy age structure survivorship curve FIGURE 19-1 A population can be widely distributed, as Earth’s human population is, or confined to a small area, as species of fish in a lake are. Copyright © by Holt, Rinehart and Winston. All rights reserved. 382 CHAPTER 19 If the small patch contains 25 oaks, an area 10 times larger would likely contain 10 times as many oak trees. A similar kind of sampling technique might be used to estimate the size of the pop- ulation shown in Figure 19-2. To use this kind of estimate, the sci- entist must assume that the distribution of individuals in the entire population is the same as that in the sampled group. Estimates of population size are based on many such assumptions, so all esti- mates have the potential for error. Population Density Population density measures how crowded a population is. This measurement is always expressed as the number of individuals per unit of area or volume. For example, the population density of humans in the United States is about 30 people per square kilome- ter. Table 19-1 shows the population sizes and densities of humans in several countries in 2003. These estimates are calculated for the total land area. Some areas of a country may be sparsely popu- lated, while other areas are very densely populated. Dispersion A third population property is dispersion (di-SPUHR-zhuhn). Dispersion is the spatial distribution of individuals within the popu- lation. In a clumped distribution, individuals are clustered together. In a uniform distribution, individuals are separated by a fairly con- sistent distance. In a random distribution, each individual’s location is independent of the locations of other individuals in the popula- tion. Figure 19-3 illustrates the three possible patterns of dispersion. Clumped distributions often occur when resources such as food or living space are clumped. Clumped distributions may also occur because of a species’ social behavior, such as when animals gather into herds or flocks. Uniform distributions may result from social behavior in which individuals within the same habitat stay as far away from each other as possible. For example, a bird may locate its nest so as to maximize the distance from the nests of other birds. These migrating wildebeests in East Africa are too numerous and mobile to be counted. Scientists must use sampling methods at several locations to monitor changes in the population size of the animals. FIGURE 19-2 TABLE 19-1 Population Size and Density of Some Countries Population size Population density Country (in millions) (in individuals/km2) China 1,289 135 India 1,069 325 United States 292 30 Russia 146 8 Japan 128 337 Mexico 105 54 Kenya 32 54 Australia 20 3 dispersion from the Latin dis-, meaning “out,” and spargere, meaning “to scatter” Word Roots and Origins Copyright © by Holt, Rinehart and Winston. All rights reserved. POPULATIONS 383 The social interactions of birds called gannets, which are shown in Figure 19-3b, result in a uniform distribution. Each gannet chooses a small nesting area on the coast and defends it from other gannets. In this way, each gannet tries to maximize its distance from all of its neighbors, which causes a uniform distribution of individuals. Few populations are truly randomly dispersed. Rather, they show degrees of clumping or uniformity. The dispersion pattern of a population sometimes depends on the scale at which the popu- lation is observed. The gannets shown in Figure 19-3b are uni- formly distributed on a scale of a few meters. However, if the entire island on which the gannets live is observed, the distribution appears clumped because the birds live only near the shore. POPULATION DYNAMICS All populations are dynamic—they change in size and composition over time. To understand these changes, scientists must know more than the population’s size, density, and dispersion. One important measure is the birth rate, the number of births occur- ring in a period of time. In the United States, for example, there are about 4 million births per year. A second important measure is the death rate, or mortality rate, which is the number of deaths in a

Skip count using the group size to find the number of groups

Number Twelve Number Twelve Is Everywhere! We use the number twelve to help us do things every day. It helps us to count things, measure length, and tell time. Did you ever wonder why a year has twelve months? A ruler has twelve inches? A clock has twelve hours? How We Learned to Count. Long ago, people needed an easy way to count things. How many goats did they have? How many bricks did they need? They didn't have pencils, but they always had their fingers. How could their fingers help them count things? Your hand has four fingers and one thumb. Fingers bend into three parts. All of your finger parts add up to-twelve! To learn how people counted, use the thumb of your other hand. Count the parts of each finger. One, two, three, four, five, six. Using their fingers, people could count their farm animals. They might count six chickens, three sheep, and three goats. They had twelve animals! When their animals had babies, it was easy to count them, too. Using both hands, people could count to twenty-four. Twenty-four is two twelves! A Ruler Is Twelve Thumbs Long Fingers, and the number twelve, were also used to find length. An inch was the width of an adult man's thumb. A foot was twelve thumbs long. Soon, people cut twelve marks for thumb widths on a stick. It was easy to carry the stick. That stick was the first kind of twelve-inch ruler! Twelve Hours in a Day People used the number twelve to divide their days into parts, or hours, that they could count. In daylight, they watched the shadow of a stick or a sundial to know what hour it was. Twelve things are also called a dozen. We buy a dozen pencils in a box. We buy a dozen doughnuts or a dozen eggs. The number twelve helps us to do a dozen things every day!

Generate all of these 25 questions Part A: Each correct answer is worth 5. 1. The regular pentagon shown has a side length of 2 cm. The perimeter of the pentagon is (A) 2 cm (B) 4 cm (C) 6 cm (D) 8 cm (E) 10 cm 2 cm 2. The faces of a cube are labelled with 1, 2, 3, 4, 5, and 6 dots. Three of the faces are shown. What is the total number of dots on the other three faces? (A) 6 (B) 8 (C) 10 (D) 12 (E) 15 3. The equation that best represents \a number increased by _ve equals 15" is (A) n 􀀀 5 = 15 (B) n _ 5 = 15 (C) n + 5 = 15 (D) n + 15 = 5 (E) n _ 5 = 15 4. The line graph shows the number of bobbleheads sold at a store each year. The sale of bobbleheads increased the most between (A) 2016 and 2017 (B) 2017 and 2018 (C) 2018 and 2019 (D) 2019 and 2020 (E) 2020 and 2021 Number of 2016 2017 2018 2019 2020 Year Sale of Bobbleheads 2021 Bobbleheads 20 40 60 80 5. Starting at 72, Aryana counts down by 11s: 72; 61; 50; : : : . What is the last number greater than 0 that Aryana will count? (A) 4 (B) 5 (C) 6 (D) 7 (E) 8 6. In the diagram, \ABC = 90_. The value of x is (A) 68 (B) 23 (C) 56 (D) 28 (E) 26 Day of the Week 44° x° A B C x° 7. Which of the following values is closest to zero? (A) 􀀀1 (B) 5 4 (C) 12 (D) 􀀀4 5 (E) 0:9 Grade 8 8. A jar contains 267 quarters. One quarter is worth $0.25. How many quarters must be added to the jar so that the total value of the quarters is $100.00? (A) 33 (B) 53 (C) 103 (D) 133 (E) 153 9. A package of 8 greeting cards comes with 10 envelopes. Kirra has 7 cards but no envelopes. What is the smallest number of packages that Kirra needs to buy to have more envelopes than cards? (A) 3 (B) 4 (C) 5 (D) 6 (E) 7 10. For the points in the diagram, which statement is true? (A) e > c (B) b < d (C) f > b (D) a < e (E) a > c y x (e, f ) (a, b) (c, d ) Part B: Each correct answer is worth 6. 11. The 26 letters of the English alphabet are listed in an in_nite, repeating loop: ABCDEFGHIJKLMNOPQRSTUVWXY ZABC : : : What is the 258th letter in this sequence? (A) V (B) W (C) X (D) Y (E) Z 12. A public holiday is always celebrated on the third Wednesday of a certain month. In that month, the holiday cannot occur on which of the following days? (A) 16th (B) 22nd (C) 18th (D) 19th (E) 21st 13. A circular spinner is divided into three sections. An arrow is attached to the centre of the spinner. The arrow is spun once. The probability that the arrow stops on the largest section is 50%. The probability it stops on the next largest section is 1 in 3. The probability it stops on the smallest section is (A) 1 4 (B) 2 5 (C) 1 6 (D) 2 7 (E) 3 10 14. A positive number is divisible by both 3 and 4. The tens digit is greater than the ones digit. How many positive two-digit numbers have this property? (A) 4 (B) 5 (C) 6 (D) 7 (E) 8 15. A rectangular pool measures 20 m by 8 m. There is a 1 m wide walkway around the outside of the pool, as shown by the shaded region. The area of the walkway is (A) 56 m2 (B) 60 m2 (C) 29 m2 (D) 52 m2 (E) 50 m2 20 m 8 m 1 m Grade 8 16. The results of asking 50 students if they participate in music or sports are shown in the Venn diagram. What percentage of the 50 students do not participate in music and do not participate in sports? (A) 0% (B) 80% (C) 20% (D) 70% (E) 40% Music Sports 15 5 20 17. There are 2 3 as many golf balls in Bin F as in Bin G. If there are a total of 150 golf balls, how many fewer golf balls are in Bin F than in Bin G? (A) 15 (B) 30 (C) 50 (D) 60 (E) 90 18. In the sequence shown, Figure 1 is formed using 7 squares. Each _gure after Figure 1 has 5 more squares than the previous _gure. What _gure has 2022 squares? (A) Figure 400 (B) Figure 402 (C) Figure 404 (D) Figure 406 (E) Figure 408 Figure 1 Figure 2 Figure 3 19. Mateo's 300 km trip from Edmonton to Calgary passed through Red Deer. Mateo started in Edmonton at 7 a.m. and drove until stopping for a 40 minute break in Red Deer. Mateo arrived in Calgary at 11 a.m. Not including the break, what was his average speed for the trip? (A) 83 km/h (B) 94 km/h (C) 90 km/h (D) 95 km/h (E) 64 km/h 20. Equilateral triangle ABC has sides of length 4. The midpoint of BC is D, and the midpoint of AD is E. The value of EC2 is (A) 7 (B) 6 (C) 6:25 (D) 8 (E) 10 Part C: Each correct answer is worth 8. 21. The positive factors of 6 are 1, 2, 3, and 6. There are two perfect squares less than 100 that have exactly _ve positive factors. What is the sum of these two perfect squares? (A) 177 (B) 80 (C) 145 (D) 52 (E) 97 22. In the list p; q; r; s; t; u; v, each letter represents a positive integer. The sum of the values of each group of three consecutive letters in the list is 35. If q + u = 15, then p + q + r + s + t + u + v is (A) 85 (B) 70 (C) 80 (D) 90 (E) 75 Grade 8 23. The net shown is folded to form a cube. An ant walks from face to face on the cube, visiting each face exactly once. For example, ABCFED and ABCEFD are two possible orders of faces the ant visits. If the ant starts at A, how many possible orders are there? (A) 24 (B) 48 (C) 32 (D) 30 (E) 40 A D B C E F 24. The number 385 is an example of a three-digit number for which one of the digits is the sum of the other two digits. How many numbers between 100 and 999 have this property? (A) 144 (B) 126 (C) 108 (D) 234 (E) 64 25. Student A, Student B, and Student C have been hired to help scientists develop a new avour of juice. There are 4200 samples to test. Each sample either contains blueberry or does not. Each student is asked to taste each sample and report whether or not they think it contains blueberry. Student A reports correctly on exactly 90% of the samples containing blueberry and reports correctly on exactly 88% of the samples that do not contain blueberry. The results for all three students are shown below. Student A Student B Student C Percentage correct on samples 90% 98% (2m)% containing blueberry Percentage correct on samples 88% 86% (4m)% not containing blueberry Student B reports 315 more samples as containing blueberry than Student A. For some positive integers m, the total number of samples that the three students report as containing blueberry is equal to a multiple of 5 between 8000 and 9000. The sum of all such values of m is (A) 45 (B) 36 (C) 24 (D) 27 (E) 29

1. How many pillars of Islam are there in total? A) Three B) Five (Correct) C) Six D) Seven Hint: Think about the famous Hadith of Gabriel where he asks about the basic practices of Islam. 2. What is the first pillar of Islam? A) Salah (Prayer) B) Zakat (Charity) C) Shahadah (Declaration of faith) (Correct) D) Sawm (Fasting) Hint: It is the declaration that there is no god but Allah and Muhammad is His messenger. 3. How many times a day must a Muslim perform Salah (prayer)? A) Three times B) Five times (Correct) C) Four times D) Six times Hint: Count Fajr, Dhuhr, Asr, Maghrib, and Isha. 4. What does the word 'Zakat' mean in terms of practice? A) Fasting all day B) Giving charity to the poor (Correct) C) Traveling to Makkah D) Reading the Quran Hint: It involves sharing a small part of your saved wealth to purify the rest of it. 5. During which Islamic month do Muslims fast (Sawm)? A) Muharram B) Ramadan (Correct) C) Shawwal D) Dhul-Hijjah Hint: It is the month in which the Quran was first revealed. 6. Where must a Muslim go to perform Hajj? A) Madinah B) Jerusalem C) Makkah (Correct) D) Cairo Hint: This city contains the Kaaba, the direction Muslims face during prayer. 7. Which pillar of Islam directly trains a Muslim in patience and feeling the hunger of the poor? A) Shahadah B) Sawm (Fasting) (Correct) C) Salah D) Hajj Hint: It is done during the daylight hours of Ramadan. Part 2: Pillars of Iman (أركان الإيمان) 8. How many pillars of Iman (faith) are there? A) Five B) Six (Correct) C) Four D) Eight Hint: It is one more than the number of pillars of Islam. 9. What is the first and most important pillar of Iman? A) Belief in Angels B) Belief in Allah (Correct) C) Belief in the Books D) Belief in the Last Day Hint: This is the belief in Monotheism (Tawhid). 10. Muslims believe that angels are created from what? A) Fire B) Clay C) Light (Correct) D) Water Hint: Think of a bright source that illuminates the dark, which matches their pure and luminous nature. 11. Which angel was responsible for bringing the revelation (Quran) to the Prophet Muhammad? A) Angel Mikaeel (Michael) B) Angel Jibreel (Gabriel) (Correct) C) Angel Israfeel D) Angel Malak al-Mawt Hint: He is the leader of all angels and visited the Prophet in the cave of Hira. 12. Belief in the Holy Books is a pillar of Iman. Which book was given to Prophet Isa (Jesus)? A) The Torah B) The Zabur C) The Injeel (Correct) D) The Quran Hint: The English translation often links this word closely to the 'Gospel'. 13. Who is the final Prophet and Messenger sent by Allah to mankind? A) Prophet Ibrahim (Abraham) B) Prophet Musa (Moses) C) Prophet Muhammad (Correct) D) Prophet Nuh (Noah) Hint: He was born in Makkah and received the Quran. 14. What does 'Belief in the Last Day' mean? A) Belief in the last day of Ramadan B) Belief in the Day of Judgment (Correct) C) Belief in the weekend D) Belief that the sun will never set Hint: It is the day when people will be rewarded with Paradise or punished based on their deeds. 15. What is the sixth pillar of Iman? A) Belief in Qadar (Divine Decree/Fate) (Correct) B) Belief in Hellfire C) Belief in the Companions D) Belief in Charity Hint: It relates to destiny and accepting whatever Allah has written for us. 16. What is the Arabic word for the 'Divine Decree' or destiny in the pillars of Iman? A) Zakat B) Qadar (Correct) C) Injeel D) Tawhid Hint: It sounds like 'Al-Qadr', as in the night of decree (Laylat al-Qadr). 17. Belief in Prophets includes believing in messengers mentioned in other scriptures. Who did Allah speak to directly? A) Prophet Musa (Moses) (Correct) B) Prophet Nuh (Noah) C) Prophet Yusuf (Joseph) D) Prophet Yunus (Jonah) Hint: He is the prophet associated with Mount Sinai and parting the sea. Part 3: Ihsan (الإحسان) 18. What is the meaning of 'Ihsan' according to the famous Hadith? A) To give all your money away B) To worship Allah as if you see Him (Correct) C) To memorize the whole Quran D) To fast twice a week Hint: It is the highest level of religion, focusing on absolute perfection and sincerity in worship. 19. If you cannot see Allah during worship, what must you always remember according to Ihsan? A) That other people are watching you B) That Allah sees you (Correct) C) That you should finish quickly D) That the angels will pray for you Hint: Allah is All-Seeing (Al-Baseer) and All-Knowing (Al-Aleem). 20. Which of the following represents the correct order of levels in religion from lowest to highest? A) Ihsan, then Iman, then Islam B) Islam, then Iman, then Ihsan (Correct) C) Iman, then Islam, then Ihsan D) Islam, then Ihsan, then Iman Hint: Every Muhsin (person of Ihsan) is a Mu'min (person of Iman) and a Muslim, but not vice versa.

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