Use Virtual$-$Work to determine the vertical deflection at midspan of $AB.$ Member $BC$ is an

axial$-$only member $($bar$),$ and member $AB$ is a beam $($no axial deformation$).$ Assume

members at joint $C$ are hinge$-$connected. Boundary conditions at both A and $C$ are pinned.

$E=29000$ksi

$A_{BC}=8\mathrm{.}4i{n}^2$

$I_{AB}=278\mathrm{.}3i{n}^4$