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A train is approaching you at very high speed as you stand next to the tracks. Just as an observer on the train passes you, you both begin to play the same recorded version of a Beethoven symphony on identical MP3 players. (a) According to you, whose MP3 player finishes the symphony first? (b) What If? According to the observer on the train, whose MP3 player finishes the symphony first?
(c) Whose MP3 player actually finishes the symphony first?