"Keeping Cool"

17. 17. Which is the best summary of the passage?

• A. Koalas are furry mammals that can be found in Australia. Over the years scientists have learned a great deal about these tree-dwelling animals. For example, scientists know that koalas eat eucalyptus and hug tress.

• B. Scientists wondered why koalas grasp the lower trunks of eucalyptus trees when the temperature rises. By using technology to study koalas, scientists discovered that doing so allowed the koalas to conserve the water in their bodies.

• C. Scientists used technology to observe koalas that hug trees. The scientists located the animals with radio tags, took photographs of them, and measured their temperatures.

• D. It is difficult for koalas to live in hot environments because they cannot sweat. They can lick themselves or pant, but these methods can cause them to become dehydrated.

18. Which sentence states the central idea of the passage?

• A. Koalas can dehydrate while trying to stay cool.

• B. Studying koalas requires special equipment.

• C. Searching for water is a dangerous activity for koalas.

• D. Changes in temperature affect the behavior of koalas.

19. According to the passage, why did the tree trunk appear darker in the thermal image?

• A. to make the koala easier to see

• B. to show it absorbs heat from the koala

• C. to represent its cooler temperature

• D. to illustrate the water inside the tree trunk

20. What is the meaning of the word verified as it is used in paragraph 5?

• A. proved

• B. compared

• C. doubted

• D. suspected

21. How does paragraph 6 contribute to the overall structure of the passage?

• A. It shows how koalas are different from other Australian animals.

• B. It describes how koalas find food, water, and shelter in a hot environment.

• C. It identifies the steps or stages of a koala's life cycle.

• D. It explains how koalas solve the problem of staying cool on hot days.