A catchment area of 60 ha has a run off coefficient of 0.40. If a storm of intensity 3 cm/h and duration longer than the time of concentration occurs in the catchment, then what is the peak discharge?

Correct option is A

​$$\text{Given: } A = 60\ \text{ha} = 60\times10^4\ \text{m}^2 = 600000\ \text{m}^2,\quad C=0.40,\quad i=3\ \text{cm/h}=0.03\ \text{m/h}.\\[6pt]\text{Convert intensity to m/s: } i = \frac{0.03}{3600} = 8.333\overline{3}\times10^{-6}\ \text{m/s}.\\[6pt]\text{Rational formula: } Q = C\,i\,A.\\[6pt]Q = 0.40 \times (8.333\overline{3}\times10^{-6}) \times 600000 = 2.0\ \text{m}^3/\text{s}.$$​​