How to solve

Member $(1)$ has a cross$-$sectional area of $0\mathrm{.}8i{n}^2{?}^2$ and a yield strength of $51$ ksi $.$ Member $(2)$ has a cross$-$sectional area of $2\mathrm{.}1in.{?}^2$ and a yield strength of $34$ ksi $.$ A factor of safety of $1\mathrm{.}9$ with respect to yield is required for both members. Use dimensions of $a=66in.,b=31$ in$.,c=60in.,$ and $d=80in.$ Determine the maximum allowable load $P$ that may be applied to the assembly. Report the factors of safety for both members at the allowable load.