Four small disks A, B, C, and D can slide freely on a frictionless horizontal surface. Disks B, C, and D are connected by light rods and are at rest in the position shown when disk B is struck squarely by disk A, which is moving to the right with a velocity v0 = (38.5 ft/s)i. The weights of the disks are WA = WB = WC = 15 lb, and WD = 30 lb. Knowing that the velocities of the disks immediately after the impact are vA = vB = (8.25 ft/s)i, vC = vC i, and vD = vD i, determine 

(a) The speeds vC and vD, 

(b) The fraction of the initial kinetic energy of the system which is dissipated during the collision.

3 ft 3 ft