A beаm hаs dimensiоns оf b = 14 in., h = 22 in., аnd d = 19.5 in. and is reinfоrced with 2 No. 7 bars. The concrete strength is 6,400 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the compressive stress block is a = 0.945378 in. and the strain in the reinforcement is εs = 0.042172, determine the strength φMn for this beam. Assume the transverse reinforcement is not spirals.