A scuba diver dove from the surface of the ocean to an elevation of −69 9/10
feet at a rate of −21.5 feet per minute. After spending 12.5 minutes at that elevation, the diver ascended to an elevation of −38 9/10
feet. The total time for the dive so far was 19 1/8
minutes. What was the rate of change in the diver's elevation during the ascent? Round your answer to the nearest hundredth.