Light moving through the lens bends and changes the color of the coin.

A Light moving through the lens makes the coin grow larger.

Light moving through the lens creates a shadow on the coin.

Light moving through the lens bends to make the coin appear larger.

Shadows are longest in the early morning, get shorter, and then get longer again in the afternoon.

Shadows are longest in the early morning and shortest in the afternoon.

Shadows are shortest in the early morning and longest in the afternoon.

Shadows are shortest in the early morning, get longer, and then get shorter again in the afternoon.

The rock layers absorbed river water over time, causing the canyon.

Layers of sediment from the river were added to the canyon’s walls.

The flowing river weathered and carved through the canyon’s rocks.

River water evaporated over time, leaving behind the canyon.

Oil and gas can leak into surrounding groundwater.

Bees and butterflies can be harmed by radio waves.

Flying birds can be hit and killed by the moving oil and gas.

Surface soil can be washed away by water more easily.

seaweed

icefish

tuna

parrotfish

Change the seat coverings from cloth to plastic.

Add additional airbags to locations where injuries often happen.

Paint the cars a different color. 

Change the shape of the blinker lights to signal turning.

Paint the cars a different color. 

Change the shape of the blinker lights to signal turning.

Change the cars so that they do not need fossil fuels to run.

Change the seat coverings from cloth to plastic.

Oak trees once grew in the area where the fossilized leaves were found.

The area where the fossilized leaves were found was once covered by a forest.

The desert air changed the leaves into fossils.

Desert plants started to grow near the fossils 150 million years ago.

large river

desert

rainforest

continent border

The inner core is the thickest layer, while the crust is the thinnest layer.

The mantle is the thickest layer, while the crust is the thinnest layer.

The mantle is the thickest layer, while the inner core is the thinnest layer.

The crust is the thickest layer, while the inner core is the thinnest layer.

Potential energy; decrease the amount of twists in the rubber band.

Kinetic energy; decrease the amount of twists in the rubber band.

Potential energy; increase the amount of twists in the rubber band.

Kinetic energy; increase the amount of twists in the rubber band.

Potential energy increases.

Kinetic energy decreases.

Kinetic energy changes to potential energy.

Potential energy changes to kinetic energy.

Wind is a nonrenewable resource because it comes from the sky.

Wind is a renewable resource because it can only be used when it is windy.

Wind is a nonrenewable resource because moving air cannot be reused.

Wind is a renewable resource because moving air cannot be used up.

Wave C has the shortest wavelength, and wave A has an amplitude larger than wave B.

Wave A and wave B have the same amplitude, and wave A and wave C have the same wavelength.

Waves A, B, and C have the same size wavelength, and wave B has the smallest amplitude.

Wave B has an amplitude twice as big as wave C, and wave A has a wavelength half the length of wave C.

It will remain unchanged.

It will decrease.

It will increase.

It will go extinct.

Two students shine their flashlights through a lens held in front of the screen, while the other flashlight is aimed directly underneath the screen.

All three students shine their flashlights at the same spot on the screen.

All three students hold mirrors in front of their flashlights.

One student shines the flashlight through a prism, while the other two shine their flashlights right at the screen.

Humans eat only animals.

Humans eat plant-eating animals but not animal-eating animals.

Humans eat plants and other animals, but no other animals eat humans.

Humans eat only plants.