What are the answers and reasoning?

B) Both rocks have the same speed when they reach the ground.

E) When they reach the ground, the heavier rock has more kinetic energy than the lighter rock.

Explanation:

Potential energy is mass times acceleration due to gravity times height.

PE = mgh

Kinetic energy is half the mass times the square of the speed.

KE = ½ mv²

Both rocks start at the same height.  Since the heavier rock has more mass, it has more potential energy. (D is false)

The rocks fall at the same acceleration and from the same height, so they reach the ground at the same time, and with the same speed (B is true, C is false).  Since the heavier rock has more mass, it has more kinetic energy (E is true, A is false).

3.2x10^7