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Directions: Use the information below and your knowledge of science to answer questions below.
An explorer on a distant planet finds an alien machine. One large part of the machine is a large ball on a rod that revolves quickly around the machine. The explorer decides to time how long it takes the ball to make one complete revolution. He starts a stopwatch when the ball is directly in front of him, and he finds that the ball is in front of him again when the stopwatch shows 12 minutes, again at 24 minutes, and again at 36 minutes.
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