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)

What happens to the light rays when they hit the specimen?

How would a small bar magnet be oriented when placed at position x?

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !