The area of square $$\(A B C D\)$$ is 144 . The respective midpoints of $$\(\overline{A B}\)$$ and $$\(\overline{B C}\)$$ are $$\(E\)$$ and $$\(F\)$$, as shown. If $$\(B\)$$ is the center of quarter-circle $$\(\overline{E F}\)$$ and $$\(C\)$$ is the center of quarter-circle $$\(\overline{B D}\)$$ then how long is a radius of the circle centered at $$\(O\)$$ that is tangent to $$\(\overline{C D}, \overline{E F}\)$$, and $$\(\overline{B D}\)$$, as shown?

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