$\begin{array}{1 1} \frac{10}{\pi}\big(\frac{\pi}{50}\big)^{\frac{2}{3}}cm \\ \frac{100}{\pi}\big(\frac{\pi}{20}\big)^{\frac{2}{3}}cm \\ \frac{100}{\pi}\big(\frac{\pi}{50}\big)^{\frac{2}{3}}cm \\ \frac{100}{\pi}\big(\frac{-\pi}{50}\big)^{\frac{2}{3}}cm \end{array} $