Oops guess we need a question.<br />
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Ok - every morning this young man gets up, gets dressed has his breakfast, walks out of his apartment, gets on the elevator, rides down  to the main floor, walks out of the building and goes to work.<br />
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Every evening this same young man enters his building, gets on the elevator, presses the button for the 12th floor, gets out on that floor and walks up the last 8 flights of stairs to his apartment.  He is not a fitness buff so why does he do this at the end of a long, hard day?