One small piece of putty m is thrown down from point A with initial downwards velocity v. A second small piece of putty also of mass m is thrown up from point B at the same time but with initial velocity 2v. Point A is h meters above point B. The pieces of putty collide and stick together. Assume the collision point occurs while the second piece is still traveling upwards. How high above point B does the combined piece of putty reach? Take v = 8 m/s, g = 10 m/s², h = 20 m, Express answer in cm.