A street performer tosses a ball straight up into the air (event 1) and then catches it in his mouth (event 2) For each of the following observers state whether the time they measure between those two events is the proper time or the dilated time: (a) the street performer; (b) a stationary observer on the other side of the street; (c) a person sitting at home watching the performance on TV; (d) a person observing the performance from a moving car.
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