Question $2(20$ Points$)$

Given $\backslash (\backslash$mathrm$\{$El$\}=1000\backslash$mathrm$\{$kN$\}.\backslash$mathrm$\{$m$\}^\{2\}\backslash )$ for the frame BCDE and $\backslash (\backslash$mathrm$\{$EA$\}=400\backslash$mathrm$\{$kN$\}\backslash )$ for the truss member AB $.$ The degrees of freedom for the whole structure is shown in the figure below,

$($a$)$ Calculate the internal normal force in the member $\backslash ($ A B $\backslash )(6$ points$)$

$($b$)$ Calculate the support reaction at E $(6$ points$)$

$($c$)$ Calculate the support reactions at D $(8$ points$)$