8.42. A ball of mass m is dropped from a height h onto a horizontal surface. Show that the vertical height through which the ball rises before it stops rebounding is h(1 + e)/(1 e?), where e is the coef- ficient of restitution. 8.43. Show that the loss in kinetic energy when two objects collide is V(1 - e?), where u is the re- duced mass, V is the relative speed before collision, and e is the coefficient of restitution.