pls answer this wirh a detailed solution:

18. A thin wire Of length l and mass m is bent in the form of a semicircle as shown. Its moment of inertia about an axis joining its free ends will be ​


$$\begin{gathered} \left(1\right) {\mathrm{ml}}^2 \left(2\right) \mathrm{Zero} \\ \left(3\right)\frac{ {\mathrm{ml}}^2}{{\mathrm{\pi }}^2} \left(4\right)\frac{ {\mathrm{ml}}^2}{2{\mathrm{\pi }}^2} \end{gathered}$$