A simply supported beam AB of span length 4m supports a uniformly distributed load of intensity q = 4 kN/m spread over the entire span and a concentrated load P = 2kN placed at a distance of 1.5 m from left end A. The beam is constructed of a rectangular cross-section with width b = 10 cm and depth d = 20cm. Determine the maximum tensile and compressive stresses developed in the beam due to bending.