The internal shear force V at a certain section of an aluminum beam is 12.8 kN. If the beam has the cross section shown (assume a=28 mm, bf=76 mm, tw=t,=6 mm, d=87 mm), determine: (a) the shear stress zy at point H, which is located 28 mm above the bottom surface of the tee shape. (b) the maximum horizontal shear stress max in the tee shape. H d V a Answers: (a) TH = MPa. (b) max = i MPa