A lever must have a fulcrum . It helps you lift stuff. A lever is a simple machine. A lever is a useful machine. A lever has to be a etched to a machine
You push a lever down four feet! They were made 440 million years ago . People have used them two hundred thousand years ago !They were began in 200 b c.People starting using levers about 17,000 b c ago.
Animals have levers in them Balance scale Balance beam