Columns and Other Compression Members

A square column with dimension of $300mm$ has the following properties: Modulus of Elasticity $=2900$ksi, Yield Strength $=35,000,$ Length $=15m,$ Moment of Inertia $=37\mathrm{.}7{10}^{6}m{m}^4.$ Determine the Euler critical load of the column. Also determine the allowable compressive stress if the column is fixed at both ends $($theoritical$).$

Is column a tension member?

Find the slenderness ratio if the critical stress is $145{10}^{6}Pa$ with $E=200,000$MPa and $I=20x{10}^{6}m{m}^4$

Determine the slenderness ratio of the column if it is fixed at one end and hinged at the other end. Cross$-$sectional area is $5500m{m}^2,L=5m,E=200$GPa,$I=20{10}^{6}m{m}^4$

Determine the allowable compressive stress of the column if it is fixed at both ends.