Withdraw Money
Use Case Scenario for a simple ATM system
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The Customer types his PIN number into the Keypad of the ATM machine.
The Little Man reads the PIN number on his Screen, verifies it, then
presents a menu of choices on the User Screen.  The Customer chooses
the "Withdraw" option.  The Little Man uses his keypad to ask how
much.  The Customer types in the amount.  The Little Man counts out
the desired amount of Cash and places it in the Cash Hopper.  The
Little Man opens the Cash Hopper and the Customer takes his cash.
