A 0.12 kg object makes an elastic head-on collision with a 0.18 kg stationary object. The final velocity of the 0.12 kg object after the collision is 0.048 m/s in the direction opposite its initial movement. The final velocity of the 0.18 kg object after the collision is 0.19 m/s in the same direction as the object which strikes it. What was the initial velocity of the 0.12 kg object?