Two full$-$sized a $c-mm$ boards are nailed to $abc-mm$ board and the resulting beam that is subjected to a vertical shear of $1600N.$ Knowing that the allowable shearing force in each nail is $355N,$ determine the allowable spacing $s$ that can be used between each pair of nails. Asume $a=55mm,b=55mm$ and $c=95mm.$

The centroidal moment of inertia, of the cross$-$section, is given as ${10}^{-6}(m^4)$

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