The beam with rectangular cross$-$section $bh$ having dimensions $b=25mm,$ and $h=50mm,$ of length $L=2m$ is supported by the three columns as shown in Figure $3.$ The continuous beam, having two spans each of the length $L_s=1m$ carries a moment of magnitude $M_0=1kNm$ acting at the distance $a=300mm$ from the support at $A$ on the first span, and the second span is loaded by a uniformly distributed load of $10k\frac{N}{m}$ over the full length $L_s.$ All supports are levelled except for the support $C$ that was propped upwards by the displacement

$u=2mm.$

Compute the stress developed in each column.

Assume: $E=2\mathrm{.}1{10}^5$MPa, all columns have the same length, and diameter $d=25mm$

$(35$ marks$)$