What is the area of a circle with a diameter of 16?

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8\pi

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16\pi

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128\pi

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256\pi
What is the area of a circle with a diameter of 16?
8\pi
16\pi
128\pi
256\pi
The formula for the area of a circle is
\pi r^2
r=\dfrac{d}{2}=\dfrac{16}{2} =8
So the area of the circle is
\pi r^2
= \pi 8^2
=64\pi