$3.$

$\backslash$begin$\{$tabular$\}\{|$c$|$c$|$c$|$c$|\}$

$\backslash$hline Member mark & $\backslash$begin$\{$tabular$\}\{$c$\}$

Member Force $($kN$)\backslash \backslash$

$\backslash ((+$: $\backslash )$ Tension $\backslash \backslash$

$\backslash (-$: $\backslash )$ Compression $\backslash ()\backslash )$

$\backslash$end$\{$tabular$\}$ & Member mark & $\backslash$begin$\{$tabular$\}\{$c$\}$

Member Force $($kN$)\backslash \backslash$

$\backslash ((+$: $\backslash )$ Tension $\backslash \backslash$

$\backslash (-$: $\backslash )$ Compression $\backslash ()\backslash )$

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline AB & $-23\mathrm{.}8$ & BC & $-23\mathrm{.}8\backslash \backslash$

$\backslash$hline CD & $31\mathrm{.}1$ & DE & $70\backslash \backslash$

$\backslash$hline AE & $-45$ & AD & $-38\mathrm{.}9\backslash \backslash$

$\backslash$hline BD & $40$ & & $\backslash \backslash$

$\backslash$hline

$\backslash$end$\{$tabular$\}$