Which of these explains how a trench can form?
A: two oceanic plates converging

If a class wants to measure the speed of a bicycle during an outdoor lab exercise, which two devices would be most useful?
A: stopwatch and tape measure

A student flips a coin four times. It lands "heads" up three times. The student concludes that the coin will land "heads" up three times out of four. What will make the conclusion more accurate?
A: flipping the coin twenty more times

Toads lay their eggs in ponds. Tadpoles hatch from the eggs and eat the plants floating in the pond. Which resource is most important for toads to survive?
A:
water