A tuber steel sturt, outside diameter 44.5 mm and wall thickness 2.5 mm, is loaded axially. the ends of the sturt are 2.7 m apart and are pin ended. Determine the buckling load using the euler formula and rankine-gordon formula. re-calculate the buckling load if the length of the strut is reduced to 1.5 m. yield stress of the material 324 MPa. E=200 GN/m^2.