Design the rectangular beam for tension only using $\frac{O}{?}=$

diameter Reinforcing steel bar to carry

dead load moment of $70$ kNm $($including the weight of the beam$)$ and a live load of $50$ kNm $.$ Use $f_y=$

$276$ MPa and $f_c^{\text{'}}=21$MPa.

Note: for the beam proportion you can use $d=1\mathrm{.}50b-1\mathrm{.}75b$