Continuous cable ADB runs over a small frictionless pulley at $D$ to support beam OABC that is part of an entrance canopy for a building $($see figure$).$ Assume that the canopy segment has a weight $W=1,800$ Ib$.$

$($a$)$ Find the required cross$-$sectional area of cable ADB $($in square inches$)$ if the allowable stress is $22$ksi.

$$ in$.2$

$($b$)$ Determine the required diameter $($in inches$)$ of the pins at $O,A,B,$ and $D$ if the allowable stress in shear is $13$ksi. $($Assume single shear in the pins.$)$

$d_O=$

$d_A=in.$

$d_B=$

$d_D=$

$in.$

$in.$