Starting from rest, a 1.9x10-4 kg flea springs straightupward. while the flea is pushing off from the ground, the groundexerts an average upward force of 0.41 n on it. this force does1.8x10-4 j of work on the flea. (a)what is the flea's speed when it leaves the ground? (b) how far upward does the flea move while it ispushing off? ignore both air resistance and the flea's weight.

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?