A 0.145 kg baseball is pitched 42 m/s The batter hits it horizontally to the pitcher at 58 m/s A) Find the change in momentum of the ball B) If the ball and bat are in contact for 4.6 x 10 exponent -4 seconds what is the average force during contact?

use p=mv, I=p_2-p_1 and I=Ft.

This should answer all your questions.

yup for impulse here's an easier equation to remember

F.dt=dp
or

F*(change in time)=(change in momentum)
impulse=(change in time)/(change in momentum).