USE MOHRS CIRCLE!!!

PROBLEM $7\mathrm{.}19$ Two wooden members of $80120-mm$ uniform rectangular cross section are joined by the simple glued scarf splice shown. Knowing that $=22$ and that the maximum allowable stresses in the joint are, respectively, $400$kPa in tension $($perpendicular to the splice$)$ and $600$kPa in shear $($parallel to the splice$),$ determine the largest centric load $P$ that can be applied.