Alex has to pick up a 20 N stack of documents and raise them 5 meters from the floor.

A. How much work does Alex do on the stack of documents as he lifts it?

B. While Alex is holding the documents, what type of energy do they have relative to the floor?

C. Alex gets tired and drops the documents to the floor. As the stack falls, what type of energy does it possess?

Simon is writing a story about an astronaut whose spacecraft has been boarded by space pirates. the astronaut has her lucky penny in her hand behind her back as the space pirates break into the control room. she has just locked the controls so that the ship is accelerating in the direction of the control room’s ceiling. simon wants the astronaut to use the penny to hit a button on the control panel to turn off the lights and escape. the button is located a short distance behind and below the astronaut’s hands. how should simon use the theory of relativity to describe what the astronaut must do in order to hit the button?