Problem $4\mathrm{.}35$

Column $AB$ is made from high strength pre$-$cast concrete and reinforced with four $\frac{3}{4}$ in$.$ diameter A$-36$ steel rods. The allowable normal stress for the high strength concrete and the steel are $({}_{\text{a}\text{l}\text{l}\text{o}\text{w}}{)}_{\text{c}\text{o}\text{n}}=1\mathrm{.}8$ksi and $({}_{\text{a}\text{l}\text{l}\text{o}\text{w}}{)}_{st}=24$ksi, respectively. The modulus of elasticity for high strength concrete is $4\mathrm{.}2{10}^3$ksi and for A$-36$ steel is $29{10}^3$ksi. $($Figure $1)$

Figure $1$ of $1$