46. ___
A. To show the relationship between fearfulness and environment.
B. To give examples of animals that aren’t fearful.
C. To compare fear in mammals to fear in other animals.
D. To identify the nerves that control fear in certain animals.
47. ___
A. Why water flows from artesian springs.
B. How artesian wells are drilled.
C. Why artesian springs are important to geologic research.
D. How aquifers are formed.
48. ___
A. They pump water from the aquifer.
B. They purify the water in the aquifer.
C. They store excess water from the aquifer.
D. They trap water in the aquifer.
49. ___
A. By eroding layers of sediment above it.
By traveling through cracks in layers of rock.
C. By reversing its flow down the aquicludes.
D. By boiling up through pores in the aquifer.
50. ___
A. It pushes the water upward.
B. It keeps the water cool.
C. It holds the water underground.
D. It creates holes in the aquiclude.
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