We consider the truss structure shown below, which has a pin support at $B$ and a roller

support at A$.$

$($i$)$ By considering the equilibrium of the entire truss, calculate the reaction forces at A and

B$.[3$ marks$]$

$($ii$)$ By considering the equilibrium of the joint D $,$ calculate the force $F_{AD}$ in the truss

member AD and the force $F_{CD}$ in the truss member CD $.[3$ marks$]$

$($iii$)$ By considering the equilibrium of the joint $A,$ calculate the force $F_{AC}$ in the truss

member $AC$ and the force $F_{AB}$ in the truss member $AB.[3$ marks$]$