PROBLEM $6\mathrm{.}8$

The built$-$up wooden beam shown is subjected to a vertical shear of $8$ kN $.$ Knowing that the nails are spaced longitudinally every $60$ mm at A and every $25$ mm at $B,$ determine the shearing force in the nails $($a$)$ at $A,(b)$ at $B.($Given: $I_x=1\mathrm{.}504{10}^{9}m{m}^4.)$