15 kg pool ball moving in the + direction collides with another pool ball. The collision lasts 50 ms, and the average impulsive force on the first...

A 0.15 kg pool ball moving in the + direction collides with another pool ball. The collision lasts 50 ms, and the average impulsive force on the first ball is -12 + 9.2 N. If the initial velocity of the first pool ball is what is the magnitude of its velocity after the collision?