The composite beam shown in the figure is simply supported and carries a total uniform load of 40 kN/m on a span length of 4.0 m. The beam is built of a southern pine wood member having cross-sectional dimensions 150 mm x 250 mm and two brass plates of cross-sectional dimensions 30 mm x 150 mm. (a) Determine the maximum stresses oBand oW, in the brass and wood, respectively, if the moduli of elasticity are EB = 96 GP and E, = 14 GPa. (Disregard the weight of the beam.) (b) Find the required thickness of the brass plates so that the plate and wood reach their allowable stress values, oa B = 70mpa and oaw = 8.5 MPa, simultaneously under the maximum moment. What is the maximum moment?

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