Two plates are spliced together with $3/4-$in$.-$diameter A$325-$X bolts by a butt splice as shown. Determine the tensile capacity of the splice if there are three bolts in a cross section and the member is made of A$36$ steel. The width, thickness, and total number of bolts on each side of the splice are as follows:

a$.$ w $=12$in$.,$ t $=3/4$in$.,$ N $=9$

b$.$ w $=8$in$.,$ t $=5/8$in$,.$ N $=6$