B-1. Calculate the moment of inertia of a uniform square plate of mass M and side L about one of its diagonals, with the help of its moment of inertia about  its centre of mass.

B-2. A uniform triangular mass M whose vertices are ABC has lengths $\mathcal{l}, \frac{\mathcal{l}}{\sqrt{2}}, \frac{\mathcal{l}}{\sqrt{2}}$ as shown in figure. Find the moment of inertia of the plate about an axis passing through point B and perpendicular to the plane of the plate. 



B-3 Find the moment of inertia of a  uniform half-disc about an axis perpendicular to the plane and passing through its centre of mass. Mass of this disc is M and radius is R.

B-4 Calculate the radius of gyration of a uniform circular disk of radius r and thickness t about a line perpendicular to the plane of this disk and tangent to th disk.