A secretary was leaving the office one Friday evening when she encountered Mr. Jones, the Human Resources manager, standing in front of a shredder with a piece of paper in his hand.

"Listen," said Mr. Jones, "this is important, and my secretary has already left. Can you make this thing work?"

"Certainly," said the secretary. She turned the machine on, inserted the paper, and pressed the start button.

"Excellent, excellent!" said Mr. Jones as his paper disappeared inside the machine. "I just need one copy