Which is a compound machine? a.) a broom b.) a screwdriver c.) a slide d.) a pair of scissors

Mike walks 100 meter north, then walks 30 meters south. after this, he walks another 10 meters north. what is the magnitude of his total displacement during this walk, in meters?

"an open tank has the shape of a right circular cone. the tank is 6 feet across the top and 5 feet high. how much work is done in emptying the tank by pumping the water over the top edge? note: the density of water is 62.4 lbs per cubic foot."

An object is kept at 45 m high and how much time will it take to reach the ground