It's not a machine a bullet is just metal which can kill you if it hits you in certain places...
or the wiki answer is;
A bullet is a projectile propelled by a firearm, sling, or air gun. Bullets do not normally contain explosives[1], but damage the intended target by impact and penetration. The word "bullet" is sometimes used to refer to ammunition generally, or to a cartridge, which is a combination of the bullet, case/shell, powder, and primer.
A pulley isn't a kind of simple machine, it is a simple machine
A train is not a simple machine.
IT's NOT A SIMPLE MACHINE!
its not a simple machine
It is a simple lever.
Rope is not a simple machine on its own, it's a simple machine on a wheel and axle, then it's a pulley.
What kind of simple machine is a garage door
a compound machine is a combination of simple machines
lever
lever
It's a simple machine.
A lever