physics please help
posted by jason .
A 5.00 kg ball (ball 1), moving to the right at a velocity of +4.00 m/s on a frictionless table, collides head-on with a stationary 7.60 kg ball (ball 2). Find the final velocities of the balls if the collision is as specified below.
(a) elastic collision
(b) completely inelastic collision
physics please help -