iran-konkur 2017 Q121

iran-konkur · Other · konkur-riazi_1396_specialized Connected Rates of Change Reverse-Engineering a Geometric Quantity from Given Rates
121. The volume of a sphere is increasing at a constant rate of $3$ cubic centimeters per second. At the moment when the radius of the sphere is $8$ centimeters, the surface area of the sphere increases how many square centimeters per second?
(1) $1/2$ (2) $1/25$ (3) $1/5$ (4) $1/6$
\textbf{121.} The volume of a sphere is increasing at a constant rate of $3$ cubic centimeters per second. At the moment when the radius of the sphere is $8$ centimeters, the surface area of the sphere increases how many square centimeters per second?

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(1) $1/2$ \hfill (2) $1/25$ \hfill (3) $1/5$ \hfill (4) $1/6$

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