5. (Hibbeler 12-20). Use the portal method to approximate the moments at all joints of the frame and then draw the approximate moment diagram for the frame. Assume that the supports at A and D are a) pinned, b) fixed, and c) partially fixed such that the inflection point for the columns is located h/3 = 6ft up from A and D. 10k B 18 ft -12 ft. C