A ball of mass m=0.8kg is tied to the end of a string of length L=0.2m and released when the string is held horizontally. Only gravity does work on the ball as it follows a circular path (tension is perpendicular to the direction of motion and so does work zero). When the ball reaches its lowest point, it collides perfectly elastically with a block of mass M=0.5kg at rest. The coefficient of friction between the block and ground is mk=0.8. How far will the block slide to the right before coming to rest?