Collisions in One Dimension?

On a frictionless horizontal air table, puck A (with m 0.249 ) is moving toward puck B (with m 0.373 ), which is initially at rest. After the collision, puck A has velocity 0.124 to the left, and puck B has velocity 0.655 to the right. What was the speed of puck A before the collision? Calculate , the change in the total kinetic energy of the system that occurs during the collision.