A 300 kg grand piano is pushed up a 4 meter ramp into the back of a truck using 1200 Newtons of force. The bed of the truck is 1.25 meters off the ground. How efficient is the piano mover that pushed the piano into the truck? (2 sig figs and answer in a percentage)

Aprisoner is forced to go into one of three rooms, but he can choose which room. the first room is ablaze with fire. the second one is rigged with explosives that will go off as soon as he enters. the third contains a pair of lions who haven't eaten in years. which room should he choose to survive?