The two$-$span steel beam shown below has a pin support at A and roller supports at $C$ and $D.$ The moment hinge at $B$ makes the beam statically determinate.

Solve for the external reactions at $A,C,$ and $D,$ as well as the hinge force at $B.$

Draw the shear diagram. Use the graphical approach described in Section $2\mathrm{.}3$ of the lecture notes.

Note that the magnitude of the hinge force at $B$ should match the shear diagram.

Draw the moment diagram using the graphical approach. Note that the internal moment should be zero at $B.$