Hemispherical end caps are welded to a cylindrical main body to form a propane storage tank. The tank has an inside diameter of d1=40in. and is to be subjected to a maximum internal pressure of p=120 psi. The allowable tensile stress in the wall of the tank is 12 ksi and the allowable tensile stress in the weld is 8 ksi.
a) Determine the minimum wall thickness Tc of the cylindrical.