screws have something called a thread, and this thread wraps around the screw. You can call the thread a kind of ramp, because this thread prevents the screw from falling off.
Caste iron
The similarities are that simple and complex machines are both made up of simple machines
That isn't a simple machine, it is a complex machine, made up of other simple machines.
Levers, Pulleys, Wheel & Axle, Inclined Planes, Wedges, and Screw.
Compound machines are things that are made up of 1 or more simple machines. A screw isn't made up of any simple machines unless you count the screw as a simple machine.
No. It's a compound machine made of two simple machines: lever and wheel & axle.
They don't have moving parts.
There isn't always a benefit to simple machines sometimes they are easier other times they need to perform hard tasks and the simple machines cant do it
compound machine
wedge and a lever and other stuff
The others are a bit more tricky.
coumpound machine