An electric motor and a single-fixed pulley work together to lift a 500 kg crate 50.0 m. how much work was done?

a) 10 j
b) 30,000 j
c) 3,000 j
d) 200,000 j

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.