one of the years before 2013
The lever is generally considered to be the first simple machine invented by humans.
the lever
The lever.
Simple machine, lever
A shifter is a lever, a lever is a simple machine
304 b.c.
No a lever is a simple machine so it's not complicated.
lever
probably the lever, which offers mechanical advantage (force multiplication)
lever
Its a simple machine which can crush any complex machine
its not a simple machine