It's in the evening, time for a grocery store to close, and a boy has just taken our groceries to the car, I guess.  Mother and Daddy and I are in a store room-like affair where the shopping baskets are kept in long diagonal rows.  There is a clock on the wall.  When the boy comes back, we thank him very much, and daddy takes out his change and sees he only has a nickel and some pennies.  He does some figuring half aloud and places a seven-cent tip on the floor by a basket.  The boy thanks us and we leave.