You are acting as bouncer at the local pub.  It is your
job to check ID’s for the servers.
   One server has placed four 3x5 cards on the bar,
describing the customers at a table in the back.
   On one side of the card is his best guess of the
patron’s age, on the other, what they are drinking.
   Should you go to the back to check some ID’s?
Whose?
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