Frank C. Mula Jr., age 11, of  South River, N. J., for his question:

What is the fastest animal on Earth?

The fastest animals are those that hunt for live food  for they must be able to catch their fast fleeing victims. We find the fastest land animal among the big cats. He is the spotted cheetah of Asia and Africa, and for a short distance he can outrun even a greyhound. At top speed, the cheetah can sprint at 70 miles an hour. He can spring into action with a mighty leap and reach a speed of 45 miles an hour in two seconds. Soon he reaches 70 miles per hour, but he can keep up this speed for only about 500 yards. So far as we know, no other land animal can run as  fast.