Four particles with masses m1 = 10 kg, m2 = 30 kg, m3 = 6 kg, and m4 = 40 kg sit on a very light (massless) metal sheet and are arranged as shown below. Find the moment of inertia of this system with the pivot at the following point. (Assume the rotation axis is parallel to the z direction, perpendicular to the plane of the drawing)