I am doing some work with tension forces and applying different masses to different items like strings. We did some things with rubber bands too. I am having trouble with one of the questions posed. "In general, in order for a rubber band to pull back, what does it have to do?" I want to say there is nothing the rubber band could do. It was made that way. So I guess they're asking that if the tension of the rubber band increased it would pull back more? Or that for a rubber band to pull back it must be strecthed?