Ball A of mass $0.5\ \text{kg}$ slides at $4.0\ \text{m/s}$ on a smooth floor towards ball B of mass $1.5\ \text{kg}$, which is at rest. Beyond B there is a fixed wall, at right angles to the motion, as shown in the figure. All collisions are head-on and elastic. Which of the following statements are correct?

Fig. 1: On a smooth floor, ball A of mass 0.5 kg moves to the right at 4.0 m/s towards a larger ball B of mass 1.5 kg, which is at rest. A fixed vertical wall stands further to the right of B.