A body `X` with a momentum `p` collides with another identical stationary body `Y` one dimensionally. During the collision, `Y` gives an impulse `J` to body `X`. Then coefficient of restitution is

A body A moving with momentum P collides one-dimensionally with another stationary body B of same mass. During impact, A gives impulse J to B. Then which of the following is/are correct ? (a) The total momentum of A and B is P before and after impact and (P - J) during the impact. (b) During the impact, B gives impulse of magnitude J to A. (c ) The coefficient of restitution is [(2J)/(P) - 1] (d) The coefficient of restitution is [(2J)/(P) + 1]