posted by Anonymous .
A softball of mass 0.220 kg that is moving with a speed of 5.5 m/s (in the positive direction) collides head-on and elastically with another ball initially at rest. Afterward it is found that the incoming ball has bounced backward with a speed of 3.9 m/s. (a) Calculate the velocity of the target ball after the collision.
(b) Calculate the mass of the target ball.