Two students are on a balcony that is 15 m above the ground. One student throws a ball vertically downward with an initial velocity of 12 m/s. Another student throws a ball upward at the same time with exactly the same speed. Both Balls eventually hit the ground below the balcony.

Question

Two students are on a balcony that is 15 m above the ground.  One student throws a ball vertically downward with an initial velocity of 12 m/s. Another student throws a ball upward at the same time with exactly the same speed. Both Balls eventually hit the ground below the balcony.
a.)What order do the balls hit, and how much time elapses between the hits? Ball A hits first and then after 2.4 seconds Ball B hits.
b.)Calculate the final velocity with which each ball hits the ground. A-46.48m/s B-?
c.)What is the distance between the two balls 0.5s after they are thrown? ???