PLEASE HELP M. A girl throws a ball 15 m into the air. The ball has the maximum potential energy at a height of a. O m.
b. 5 m.
c. 10 m.
d. 15 m.

A( developed during the process of technology design

On mars a rock falls an unknown vertical distance from a resting position and lands in a crater. if it takes the rock 2.5 seconds to fall, how high is the cliff the rock fell from? mars' surface gravity is 3.8 m/s2.

How do i solve this physics problem?