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A 1.0-kg stone and a 10.0-kg stone are released from rest at the same height above the ground. Ignore air resistance. Which of these statements about the stones are true? Justify each answer, (a) Both have the same initial gravitational potential energy, (b) Both will have the same acceleration as they fall, (c) Both will have the same speed when they reach the ground, (d) Both will have the same kinetic energy when they reach the ground.
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