19) Two objects of unequal masses, M and m (M > m), are connected by a very light cord passing over an ideal pulley of negligible mass. When released, the system accelerates, and friction is negligible. Which one of the following free-body diagrams most realistically represents the forces acting on the two objects in the moving system? A) B) C) D) M M 127 M M 20) If the units of your answer are kg . m2/s3, which of the following types of quantities could your answer be? (There could be more than one correct choice.) A) work B) power C) kinetic energy D) force E) potential energy