Total energy input is 1400 and my efficiency is 80% so what is the useful energy output in jules?

Suppose you use a machine that gives you a mechanical advantage of 2 to achieve an output force of 30newtons what must the input force be

What kind of simple machine is a catapult?

The statue of liberty is 305.5 feet high. when the angle of elevation of the sun is 50 , what is the distance to the tip of the shadow from a point at water level and directly below the highest point of the statue?