A 27 kg child goes down a straight slide inclined 38 above the horizontal, which is 2.5 m long. There is friction between the child and the slide, and the magnitude of the kinetic friction force on the child is 72 N. The child slides all the way down to the bottom of the slide. Consider the system consisting of the child and the Earth together. 38 A. Draw a free-body diagram for the child. Next to your diagram, indicate the direction of the child's displacement. B. Calculate the work done on the system by the friction force. C. Calculate the change in gravitational potential energy of the system. D. If the child starts at rest at the top of the slide, determine the speed of the child at the bottom of the slide.