The rectangular cross section in Figure $2$ is the cross section of a RC beam with a span of $5\mathrm{.}5$ m$.$ wD$20$kN$/$m$,$ wL$30$ kN$/$m$,$ and self$-$weight act on this beam. Determine the type and number of reinforcing bars to be placed in this beam. Set the strain rate of the outermost tension rebar to $0\mathrm{.}006$ and design it as double rebar if necessary.$($fck$24$MPa, fy$400$MPa$)$

Fig. $2$