Pls refer to the eurocode and give the correct answer nswer

QUESTION $1$

A steel column of section $305305158$ UC $$275$ has an effective height of $3500$ mm and is pinned at both ends as shown in Figure Q$1.$ The Factored Axial Load is $800$ kN and the Factored Moment at the top of the column is $450$ kNm $.$

You are required to carry out these checks:

a$)$ Classify the selected Steel Section for the column design.

$(5$ marks$)$

b$)$ Check the Resistance of Cross$-$sections in terms of Bending and Axial Force. $($by showing that hat$({)}_Y<mn>1</mn>$tilde$({)}_z<mn>1</mn><msub><mrow><mi>M</mi></mrow><mrow><mi>E</mi><mi>D</mi></mrow></msub>$