Apressurized ¼-inch-thick cylindrical tank is constructed with a helical weld that makes an angle  = 36.86990 with the longitudinal axis. the tank has a diameter d = 12 inch and is subjected to internal gas pressure p = 320 psi. the allowable tensile and shear stresses are 8000 and 3200 psi, respectively. also the allowable tensile stress normal to the weld is 6000 psi, and the allowable shear stress of the weld is 2800 psi. determine whether the cylindrical portion of the tank is safe. for the analysis, check the following: • the maximum principal stress criterion, • the maximum in-plane shear stress criterion, • the normal and shear stresses of the weld.