1. A 0.2 kg baseball is pitched by a pitcher with a velocity of 40 m/s. The batter hits the ball, and it travels back toward the pitcher with a final velocity of -30 m/s (negative because it's in the opposite direction). The contact time between the bat and the ball is 0.02 seconds. 

a. Calculate the change in momentum of the baseball when hit by the bat. 

b. Determine the impulse experienced by the baseball due to the hit. 

c. Find the average force exerted on the baseball by the bat during the contact time.