$(25$ points$)$ Consider the rigid body below that is fixed to the ground at point O $.$ Show all work and simplify. $F_A=30kN$ and $F_B=15kN$

A$.(9$ points$)$ Draw a free body diagram of member OAB $.$ A free body diagram includes labels, a coordinate system, all forces, relevant points, and relevant dimensions. It is also reasonably sized.

B$.(8$ points$)$ Determine the magnitude of the reaction force at point $O,R_0.$

C$.(8$ points$)$ Determine the magnitude of the reaction moment at point $0,M_0.$

$r_0=$

$u_0=$