Let $\displaystyle {A}$ be the area of a circle with radius $\displaystyle {r}$. If $\displaystyle {\frac{{{d}{r}}}{{{\left.{d}{t}\right.}}}}={2}$, find $\displaystyle {\frac{{{d}{A}}}{{{\left.{d}{t}\right.}}}}$ when $\displaystyle {r}={3}$.

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