Area. The radius, r, of a circle is decreasing at a rate of 2 centimeters per minute. Find the rate of change of area, A, when the radius is $5$ .
A) $\frac { d A } { d t } = - 10 \pi$
B) $\frac { d A } { d t } = - 100 \pi$
C) $\frac { d A } { d t } = 100 \pi$
D) $\frac { d A } { d t } = - 20 \pi$
E) $\frac { d A } { d t } = 20 \pi$

Question

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The Answer of Area. The radius, r, of a circle is decreasing at a rate of 2 centimeters per minute. Find the rate of change of area, A, when the radius is $5$ .
A) $\frac { d A } { d t } = - 10 \pi$
B) $\frac { d A } { d t } = - 100 \pi$
C) $\frac { d A } { d t } = 100 \pi$
D) $\frac { d A } { d t } = - 20 \pi$
E) $\frac { d A } { d t } = 20 \pi$

Area the Radius, R, of a Circle Is Decreasing at a Rate