Problem $8.(35$ points$)$ A truss is supported by a smooth pin $($A$)$ and a roller $($B$).$ Two loads are applied as shown. $F=300N.$

$($a$)$ Find zero$-$force member$($s$)(5$ points$)$

$($b$)$ Use a global equilibrium to find support reactions. Draw the FBD$.(15$ points$)$

$($c$)$ Find the member force in AC$.$ Draw the FBD for the joint you choose. $(15$ points$)$