Q$\mathrm{.}2)(60$ points$)$ Find length, width, and thickness of an isolated square footing to support a circular column of $40cm$ diameter, and carries a dead load of $400kN,$ and a live load of $220kN.$ Then design flexure reinforcement.

$f_c^{\text{'}}=28$MPa,$f_y=400$MPa,$q_{\text{a}\text{l}\text{l}\text{o}\text{w}}=200$KPa