A rod of length L rests on a smooth horizontal table. The mass of the rod is M. The rod can move freely across the surface of the table. A small disk of mass "m" approaches with a speed "v", as shown in the figure, and elastically collides with the rod at a distance "d" from the center. It is asked: a) What magnitudes are conserved in the collision? b) Suppose that the disk remains at rest after the collision. Calculate the mass of the disk. Do the procedure in all steps. 1 M L