研究所、轉學考(插大)-微積分題庫

【非選題】

7. Water runs into a conical tank at the rate of 9 ft³/min. The tank stands point down and has a height of 10 ft and a base radius of 5 ft. How fast is the water level rising when the water is 6 ft deep? (see the figure below) (10%)
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the conical tank in problem 7.