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AP Calculus related rates problem?
The volume V or a cone (V = 1/3 ð r² h) is increasing at a rate of 28ð cubic units per second. At the instant when the radius r of the cone is 3 units, its volume is 12ð cubic units and the radius is increasing at 0.5 unit per second.
c)At the instant when the radius of the cone is 3 units, what is the instantaneous rate of change of the area of its base with respect to its height h?
my teacher showed my how to get the answer but i don't understand why..can someone show the steps with explanation PLEASE?
..by the way the answer is 3pi/8

Ok really I don't know all of the steps but if you look at the da/dt of a) and put it over the dh/dt of b) then you get your answer. I don't know. I'm doing it right now.
God Bless!
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