CEMC Cayley, 2005

Geometry Difficulty 3.0 AMC 10/12 Find the answer Canada

In the diagram, $AOB$ is a quarter circle of radius 10 and $PQRO$ is a rectangle of perimeter 26. The perimeter of the shaded region is

(A) $7 + 5\pi$ (B) $13 + 5\pi$ (C) $17 + 5\pi$ (D) $7 + 25\pi$ (E) $17 + 25\pi$

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