Q$4.$ A four$-$member structure is under the loading as shown. $($a$)$ Determine the internal forces in

members $CB,DB,$ and $AB,$ and state whether in tension or compression. $($b$)$ Determine the reaction

forces at the supports A and $D.($c$)$ Someone claims the structure is a truss. Do you agree? Justify

your answer.

$[10$ marks$]$

Q$5.$ Draw the shear force and bending moment diagrams for the compound beam ABCDE shown.

The beam segments are connected by pins at $B$ and $D,$ with a right$-$angular rigid link to joint $D.$

Support $A$ is fixed, $C$ is a roller, and $E$ is a rocker.