A golf ball is released from rest from the top of a very tall building. Choose a coordinate system whose origin is at the starting point of the ball, and whose y axis points vertically upward. The acceleration of gravity is 9.8 m/s 2 . Neglecting air resistance, calculate the ve- locity of the ball after 3.99 s. Answer in units of m/s. 029 (part 2 of 4) 10.0 points What is its speed just before impact with the ground? Answer in units of m/s. 030 (part 3 of 4) 10.0 points Now assume the hot air balloon is traveling vertically downward at a constant speed of 4.9 m/s.