A 0.15-kg baseball traveling in a horizontal direction with a speed of 20 m/s hits a bat

Question:

A 0.15-kg baseball traveling in a horizontal direction with a speed of 20 m/s hits a bat and is popped straight up with a speed of 15 m/s.
(a) What is the change in momentum (magnitude and direction) of the baseball?
(b) If the bat was in contact with the ball for 50 ms, what was the average force of the bat on the ball?