Help to sove it

Question $2.$ A $3$ m height compression member is concentrically supported at both ends.

The cross section of the member is RHS $100505($RHS Table $1\mathrm{.}5$ of

$"$ST$$LKONSTRUKJONER$")$ of S$275$ steel grade. The member is subjected to an axial

compressive design load $(N_{Ed})$ of $150$ kN $.$ Check the suitability of the column $($i$.$e$.$ can the

column withstand the above loading$),$ when

a$)$ Both ends of the member are fixed supported.

b$)$ One end is simply supported while other end is fixed supported.

c$)$ Both ends of the member are simply supported.

d$)$ One end is fixed supported while other end is free.