1953 AHSME Problem 11

A running track is the ring formed by two concentric circles. It is 10 feet wide. The circumference of the two circles differ by about:

\begin{array}{l} \textbf{(A)}\ 10\text{ feet} \qquad \textbf{(B)}\ 30\text{ feet} \qquad \textbf{(C)}\ 60\text{ feet} \qquad \textbf{(D)}\ 100\text{ feet}\\ \textbf{(E)}\ \text{none of these} \end{array}

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.