Using rectangular section $(b={16}^{\text{'}\text{'}},h={32}^{\text{'}\text{'}}$ and $d=28")$ for the shown loaded situation below with $f_y=60,000,f_c^{\text{'}}=4000,$ assume reinforced concrete weights $150pcf.$

Find $A_s=?$ Using both quadratic and iteration method.

Please sketch your final cross section with total $A_s$ and needed dimension. Note: No need to pick bars for this homework set.