A 2.10-kg ball, moving to the right at a velocity of +4.60 m/s on a frictionless table, collides head-on with a stationary 6.30-kg ball. Find the final velocities of (a) the 2.10-kg ball and of (b) the 6.30-kg ball if the collision is elastic. (c) Find the final velocity of the two balls if the collision is completely inelastic.