In Fig. P$-2-11\mathrm{.}5,$ a boom AC is supported by a ball$-$and$-$socket joint at C and by the cables BE and AD$.$ If the force multiplier of forceF acting from B to E is Fm $=10$ lb$/$ft$,$ find $($a$)$ the moment of F aboutpoint C$,($b$)$ the moment of F about point D$,($c$)$ the moment of F about a line directed from C to D$.$