Problems: Determine the reactions and forces in all bars for the trusses shown below.

Fig. $(1)$ due to applied load, support D settles vertically $1\mathrm{.}0cm.$ EA is constant.

Fig. $(2)$ due to a temperature drop of $25C$ in bars $FE,$ and $ED$ and a temperature increase of $30C$ in member $AB,$ bar $EB$ is fabricated $100mm$ too long.

Fig. $(3)$ due to a temperature increase of $20C$ in top chords GFE, bar EC is fabricated $120mm$ too long and bar $Cl$ is fabricated $80mm$ too short.

Use $=12{10}^{-6},EA=1{10}^{5}kN$ where it is needed

Fig.$(1)$