$(1.)$ a$)$ Determine the internal force components at the section of the cantilever next to the support and sketch them in a view opposite the arrow of axis $x.$

$l=3m$

$K=14cm$

$B=12cm$

$F_z=15kN$

$F_x=10kN$

b$)$ Find magnitude and direction of the normal$-$ and shear$-$ stresses at point $A$ of the cross section next to the support.

c$)$ Find magnitude and direction of the normal$-$ and shear$-$ stresses at point $B$ of the cross section next to the support.

d$)$ Give the matrix of the stress tensor in point $A$ of the cross section next to the support in the $(x,y,z)$ coordinate$-$system!