With gyms being so expensive Raymond is finding it hard to stay ripped. Push ups aren't enough and he doesn't have room in his apartment for weights, so Raymond buys the stiffest exercise band that he can find (k =4,000 N/m). If Raymond stretches one of them 1.3 m, how much work did he perform? [Hint: Stretching an exercise band is like compressing a spring, because it stores energy/work.]