I attach a 2 kg block to a spring that obeys Hooke's Law and supply 16 J of energy to stretch the spring. I release the block; it oscillates with period .3 s. The amplitude is: * 38 cm * 19 cm * 9.5 cm * 4.3 cm Can anybody help me with this? I can't figure out what to do or where to start. It seems so easy, but I can't get it. Thanks.