$3.$ For the beam shown, determine $()/((($a$)/))$ the maximum tensile and compressive bending stresses; $()/((($b$)/))$ the maximum shear stress due to $()/(($ V $/)),$ and $()/((($c$)/))$ the maximum shear stress in the beam.

Cross section $($enlarged$)$

The figure illustrates a steel beam section. Use an allowable

bending stress of $12$ ksi for this steel beam and find the

maximum uniformly distributed load that the beam can carry if

the given length between two simple supports is $60$ in $,$ and

cross section is steel angles $2(1)/(2)\backslash$times $2(1)/(2)\backslash$times $(1)/(4)21\mathrm{.}0$lb$($f$)/($i$)$n$.$