A beam is constructed from a W shape and a C shape, both of A $36$ steel, as shown. Two

equal loads remain $3ft$ apart as they move across a $40ft$ span. Sufficient lateral support is provided so that

the allowable bending stress is $0\mathrm{.}6$ Fy$.$ The beam is not subjected to impact loading. Determine the absolute

value of the actual shear stress $($anywhere in the beam$)$ corresponding to the value of $P$ obtained in

consideration to the moment. $($Use NSCP $2010)$

$W18x119C15x33\mathrm{.}9$

$A=35\mathrm{.}1sq.inA=9\mathrm{.}96sq.in$

$d=18\mathrm{.}97in,bf=3\mathrm{.}4in$

$Ix=2190in4,tw=0\mathrm{.}40in$

$,ly=8\mathrm{.}13in4$