A beam has a rectangular section $60$ mm wide and $140$ mm deep and a span of $1$ m $.$ The beam is simply supported, carries a concentrated load of $20$ kN at midspan and is subjected to an axial compressive force of $70$ kN applied on the centroid of the cross$-$section. Calculate the following:

$2\mathrm{.}1$ Maximum resultant stress in the beam and

$15$

$2\mathrm{.}2$ Plot the stress distribution diagram for this section.

$[5]$