Q$3(30$ pts$)$: For the stem shown below find the required diameters of the steel pins at Point A and B$.$ The failure shear stress of the stress is given as $\backslash$tau $\_$yeld $=150$ M P a$.$ Use the LRFD meth$$d$,$ where the resistance factor for shear is $=0\mathrm{.}75$ and the load factors for the dead and live loads are $\backslash$gamma $\_$D$=1\mathrm{.}2$ and $\backslash$gamma $\_$L$=1\mathrm{.}6.$