50. ___
A. To keep train engines cool.
B. To preserve perishable food.
C. To store ice while it was being transported.
D. To lift blocks of ice from frozen lakes and ponds.
40. ___
A. The relationship between physics and philosophy.
B. Ancient Greek beliefs about matter and motion.
C. The effects of Aristotle's philosophy on current theories of physics.
D. Aristotle's use of fire in scientific experiments.
43. ___
A. It's pushed away from Earth by fire.
B. It's trying to return to its natural resting place.
C. It's attracted to other planets.
D. Its main substance is water.
44. ___
A. To solicit volunteers for Turtle Watch.
B. To give an assignment to a biology class.
C. To warn students not to hurt green turtles.
D. To describe the nesting and hatching activities of the green turtle.