Question $3$: $[30$ Marks$]45$ minutes

The frame supports the triangular distributed load shown in Figure $3.$

a$)$ Draw the shear and bending moment diagram for segment BC$.$

b$)$ Determine the internal forces at point D of the frame.

c$)$ Using Mohr$$s Circle, determine the normal and shear stresses at point D that act

perpendicular and parallel, respectively, to the grains. The grains at this point make an angle

of $35$ with the horizontal as shown.