PROBLEM $4.[15$ points$]$ There is a rod on the ground as shown below, which has a mass $M[$kg$],$ length $L[$m$],$ and rotational inertia at the center of mass $G,I_G[(kg)*m^2].$ As you expect, it will fall due to gravity. When there is no slip, please describe the G$\text{'}$s path during the motion. Please describe the G$\text{'}$s path when there is no friction $($Hint: Note the force and moment equations$).$