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
determine whether he gives her a tender embrace or knocks her off her limb by calculating tarzan's speed just before he reaches jane
ignore air resistance and the mass of the vine.