PLEASE ANSWER IN SEPARATE PAPER WITH COMPLETE SOLUTION.

EXAMPLE

A simply supported beam $6m$ long is composed of two $C$

$20028$ channels riveted back to back. What uniformly

distributed load can be carried, in addition to the weight of the

beam, without exceeding a flexural stress of $125M\frac{N}{m^2}$ if $($a$)$

the webs are vertical and $($b$)$ the webs are horizontal.