A vertical member $NPB|{300}^{**}150||$ of $3m$ is hanged vertically and has to carry the factored tensile load of $300kN$ through its bottom end. This member is transferring the applied load through plates $($flange cover plates$)$ bolted on both the flanges at the far end to the top main plate $($horizontally placed$),$ which is $20mm$ thick. Flange plates are bolted to the main plate through angle sections from the outer sides. The width and thickness of the flange cover plate is $45016mm,$ and the top main plate is sufficiently wide to make a connection with the flange plates. The vertical depth of the flange cover plate can be fixed per the connection requirement. A duct of $150mm$ in diameter is to be passed from the top face of NPB$.$ The only angle section available to make the connection is ISA $90908$@$10\mathrm{.}8k\frac{g}{m}.$ The grade of steel of the sections is Fe $410.$ Use a bolt of grade $4\mathrm{.}6$ and $20mm$ diameter. Ignore the effect of prying action. The moment capacity of the angle section is enough to care for any moment and, hence, does not require any attention. The properties of the NPB are tabulated below.

$\backslash$table$[[\backslash$table$[[$Beam$],[($NPB$)]],\backslash$table$[[$Mass$],[M$