A thin piece of wire 40 meters long is cut into two pieces.  One piece is used to form a circle with radius r, and the other is used to form a square.  No wire is left over.  Which of the following represents the total area, in square meters, of the circular and the square regions in terms of r?

~$\pi r^{2}$~

~$\pi r^{2}+10$~

~$\pi r^{2}+\frac{1}{4}\pi ^{2}r^{2}$~

~$\pi r^{2}+\left ( 40-2\pi r \right )^{2}$~

~$\pi r^{2}+\left ( 10-\frac{1}{2}\pi r \right )^{2}$~


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