The rigid beam is supported by three $A-36$ steel wires, each having a length of 4 ft. The cross-sectional area of $A B$ and $E F$ is 0.015 in $^{2}$, and the cross-sectional area of $C D$ is 0.006 in $^{2} .$ Determine the largest distributed load $w$ that can be supported by the beam before any of the wires begin to yield. If the steel is assumed to be elastic perfectly plastic, determine how far the beam is displaced downward just before all the wires begin to yield.