A steel pipe of 12-in. outer diameter is fabricated from 1/4in. thick plate by welding along a helix which forms an angle of 22.5 degrees with a plane perpendicular to the axis of the pipe. Knowing that a 40-Kip axial force P(downward) and an 80-kip in. torque T(counterclockwise) are applied to the pipe, determine the normal and shear stress in directions, respectively, normal and tangential to the weld. Solve this problem using Mohr's Circle.