**AMC 10 Mock Exam Question 24**

A quadrilateral is inscribed in a circle of radius $200\sqrt{2}$. Three of the sides of this quadrilateral have length $200$. What is the length of the fourth side?

$\displaystyle \textbf{(A) } 200\qquad \textbf{(B) } 200\sqrt{2}\qquad\textbf{(C) } 200\sqrt{3}\qquad \textbf{(D) } 300\sqrt{2}\qquad\textbf{(E) } 500$

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