1. A winch at the top of a 12-meter building pulls a pipe of the same length to a vertical position, as shown in the figure. The winch pulls in rope at a rate of 0.9 meter per second (ds/dt = 0.9 m/sec).

Find the rate of vertical change (in m/sec) and the rate of horizontal change (in m/sec) at the end of the pipe when y = 4. (Round your answers to three decimal places.)

2. A spherical balloon is inflated with gas at a rate of 700 cubic centimeters per minute. Find the rates of change of the radius when r = 60 centimeters and r = 85 centimeters.