A0.15 kg baseball moving at a velocity of -40 m/s collides with a 0.8 kg bat moving at a velocity of +30 m/s. if the velocity of the ball after the hit is +50 m/s, what is the final velocity of the bat? a. vf = +0.35 m/s b. vf = +13.1 m/s c. vf = +28.1 m/s d. vf = +32.3 m/s