A child in a sled is at rest on a hill. The gravitational potential energy of the child and sled at point A is 800 J. An adult pushes the child and sled to the edge of the hill (point B). At point B, the child and sled have a kinetic energy of 100 J. The combined mass of the child and sled is 20 kg. Which of the following best describes the energy change between points A and B? Potential energy transforms into kinetic energy Mechanical energy transforms into kinetic energy Energy is transferred to the child and sled by the adult

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