A cast-iron hollow-box column of length L is fixed at its base and free at its top, as d...

A cast-iron hollow-box column of length L is fixed at its base and free at its top, as depicted in Fig. P11.28. Assuming that an eccentric load P acts at the middle of side AB (that is, e = 50 mm) of the free end, determine the maximum stress in the column. Given: P = 250 kN, L = 1.8 m, E = 70 GPa, and e = 50 mm.