The structure shown is pinned together at points $A$, $B$, and $C$ and held in equilibrium by the cable $CD$. $A$ load of 12,000 lb is acting at the midpoint of member $AB$, and a load of 8000 lb is applied at point $C$.
Determine the reaction at $A$, the internal force in member $BC$, and the tension on cable $CD$.
