You are tasked with making a rubber band car. You have some wood, CD wheels, a couple of metal axles to work with. You may choose if you want to make your car go for distance or for speed, but you must state the goal. The idea will be that the rubber band will be the source
of energy in your car. Explain how you plan to make your car (including stating what sort of simple machines will be used) and state why
you feel it will accomplish the task of either traveling a great distance or traveling at a great speed. Make sure to use the language of
simple machines and energy.

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.