A rubber ball is shot straight up from the ground with speed v₀. Simultaneously, a second rubber ball at height h directly above the first ball is dropped from rest.

a. At what height above the ground do the balls collide? Your answer will be an algebraic expression in terms of h, v₀, and g.

b. What is the maximum value of h for which a collision occurs before the first ball falls back to the ground?

c. For what value of h does the collision occur at the instant when the first ball is at its highest point?