The connection shown is required to develop the design tensile strength ${}_t{P}_n$ of the A$572$ Grade $65$ stel plates $)=65$ksi,$F_y=(80$Ksi. Bolts are $\frac{3}{4}-$in$.$ diam.

$($a$)$ Find of the plates$).$

$($b$)$ If the connection is slip$-$critical with Class A faying surface, should we use A$325$ or A$490$ bolts?

$($c$)$ If the connection is bearing$-$type with threads included in the shear planes, should we use A$3$Z$5$ or A$470$ bolts? Also, make sure here that the design' bearing strength of the connection is adequate. Standard size holes.