$2.$ A preliminary design model to ensure rotational stability for a spacecraft consists of the cylindrical shell and the two square panels as shown. The shell and the panels have the same thickness and density. It can be shown that, in order for the spacecraft to have a stable spinabout axis $\backslash (1-1\backslash ),$ the moment of inertia about axis $1-1$ must be less that the moment of inertia about axis $2-2.$ Determine the critical value of $\backslash (\backslash$ell $\backslash )$ which must be exceeded to ensure stable spin about axis $1-1.$