A man and his son were traveling to the bank one Saturday morning when they stopped at a corner. The little boy hearing a "Beep..Beep..Beep" and ask his dad where the sound was coming from.
His dad replied that the sound was comming from a near by dump truck that was backing up and that sound was to warn people behind it to get out of the way.
When they arrived at the bank the lines were long (as usual) and so they got into one of the lines behind a rather large lady.
All of a sudden another man's beeper started to go off and the little boy with fear in his eyes said "Look out dad she's backing up!"