2009 Fermat Problem 17

In the diagram, the perimeter of the semicircular region is 20. (The perimeter includes both the semicircular arc and the diameter.) The area of the region is closest to

\textbf{(A)}\ 36.6\quad \textbf{(B)}\ 23.8\quad \textbf{(C)}\ 49.3\quad \textbf{(D)}\ 51.6\quad \textbf{(E)}\ 26.7

If there are no answer choices shown, enter a numerical answer.

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