Two blocks, A and B (with mass 50 kg and 100 kg, respectively), are connected by a string, as shown in Figure P5.64. The pulley is frictionless and of negligible mass. The coefficient of kinetic friction between block A and the incline is ?k = 0.25. Determine the change in the kinetic energy of block A as it moves from C to D, a distance of 15 m up the incline if the system starts from rest. ____J