You and a fellow experimenter stand alongside the tracks three kilometers from each other. When the entrance on the prepare passes you, you sign your associate. Your partner waits 89 seconds and takes note of what part of the practice now passes in entrance of him. What does he see? The end of the practice. The 4 kilometer prepare fit within the three kilometer separation between you and your fellow experimenter. That occurred because your partner regarded on the practice later than you. This is ...