a plastic ball of mass 200.0 g moves with a velocity of 30.0 cm/s. this plastic ball collides with a second plastic ball of mass 100.0 g which is moving along the same line with a velocity of 10.0 cm/s. after the collision, the velocity of the 100.0 g mass is 26 cm/s along the same line. what is the velocity of the 200.0 g mass?