This question, I have absolutely no idea what to do. Question: Tarzan, in one tree, sights Jane in another tree. He grabs the end of a vine with length 20 m that makes an angle of 45 degrees with the vertical, steps off his tree limb, and swings down and then up to Jane's open arms. When he arrives, his vine makes an angle of 30 degrees with the vertical. Part A) Calculate Tarzan's speed just before he reaches Jane. You can ignore air resistance and the mass of the vine. I figured that I am going to have to use the work energy theorm, W=change in K and then break it down into smaller bits, but there is no mass and I have no idea what work is equal to so I am totally stumped.