A 50-g ball moving at 10 m/s in the +x direction suddenly collides head-on with a stationary ball of mass 100 g. If the collision is perfectly elastic, what is the velocity of each ball immediately after the collision?A. +6.7 m/s, -3.3 m/sB. -6.7 m/s, +3.3 m/sC. +3.3 m/s, -6.7 m/sD. -3.3 m/s, +6.7 m/s