$4.$ A post with a solid circular cross section supports a load applied on a plane parallel to the yz$-$plane. The load is at an angle of $\backslash (30^\{\backslash$circ$\}\backslash )$ from a line parallel to y axis as shown in the figure below. The height of the post is $27$ ft $.$ The distance from the load application point to the centroid of the vertical part of the post is $5$ ft $.$ The diameter of the post is $4$ in $.$

$($a$)$ Clearly show the direction of each force and moment acting on the cross section where point A is located using Figure $2$ as your sketch for the cross section.

$($b$)$ Determine the magnitude of all the forces and moments acting on the cross section where point A is located.

$($c$)$ Calculate the normal stress and shear stress at point A$.$