Two identical spheres of mass M are fastened to opposite ends of a rod of length 2 L. The radii of the spheres are negligible when compared to the length 2L, and the rod has negligible mass. This system is initially at rest with the rod horizontal and is free to rotate about a frictionless axis through the center of the rod. The axis is horizontal and perpendicular to the plane of the page. A bug of mass 3M lands gently on the sphere on the left. Assume that the size of the bug is small compared with the length of the rod. After the bug lands, the rod begins to rotate. What correctly describes the change in the magnitude of the angular momentum of the bug-rod-spheres system and the change in gravitational potential energy of the bug-rod-spheres-Earth system as the rod rotates but before the rod becomes vertical?