I volunteered recently to perform a parachute jump for charity. On our first day of training, the instructor made an important point about preparing for landing at 300 feet.
"How do you know when you're at 300 feet?" asked one woman.
"A good question," replied the instructor. "At 300 feet you can recognize the faces of people on the ground."
The woman thought about this for awhile before saying, "What happens if there's no one there I know?"