Problem $4(20$ points$)$ Show your work:

For the cross section shown below, if factored ultimate shear is $160$kip, the maximum spacing, $S_{\text{m}\text{a}\text{x}}.$

allowed by ACl is most nearly:

$f_{e^{\text{'}}}=4500,f_M=60,000.$

$(2)13\mathrm{.}5$ in

b$)12\mathrm{.}0$ in

c$)6\mathrm{.}75$ in

d$)2\mathrm{.}41$ in