Time for a pop quiz.
Alligators inhabit the sewers of New York City.
The Commissioner of the U.S. Patent Office once said that everything that could be invented had been. Hair and nails continue to grow after a person dies. Metal tooth fillings can receive radio signals. The Great Wall of China can be seen from the moon by the naked eye. Grace Hopper coined the term bug after a moth was found in a relay of the Harvard Mark II computer in 1947.