Show me the steps to solve these problems $3-69.$

If $F_1=100N,F_2=120N,$ and $F_3=80N,$ determine the

magnitude and coordinate direction angles of the resultant

couple moment. $3-86.$

The belt passing over the pulley is subjected to two forces $F_1$ and $F_2,$ each having a magnitude of $40N.F_1$ acts in the $-k$ direction. Replace these forces by an equivalent force and couple moment at point $A.$ Express the result in Cartesian vector form. Take $=45.3-98.$

Replace the parallel force system acting on the plate by a resultant force and specify its location on the $x-z$ plane$\mathrm{.}3-117.$

Determine the magnitude of the equivalent resultant force and its location, measured from point $O.$