Two soils of permeabilities $\mathrm{k}_1$ and $\mathrm{k}_2$ are placed in a horizontal flow apparatus, as shown in the figure. For Soil 1, $L_1=50 \mathrm{~cm}$, and $k_1=0.055 \mathrm{~cm} / \mathrm{s}$; for Soil 2, $L_2=30 \mathrm{~cm}$, and $\mathrm{k}_2=0.035 \mathrm{~cm} / \mathrm{s}$. The cross sectional area of the horizontal pipe is $100 \mathrm{~cm}^2$, and the head difference ( $\Delta \mathrm{h}$ ) is 150 cm . The discharge (in $\mathrm{cm}^3 / \mathrm{s}$ ) through the soils is ________ (rounded off to 2 decimal places).
To derive the total flood hydrograph at a catchment outlet from an isolated storm, the order in which the following methods are applied, from the first method to the last method, is
P. Obtaining the hyetograph
Q. Addition of baseflow
R. Estimation of initial and infiltration losses
S. Application of unit hydrograph
A water resources project with an expected life of 25 years has to be designed for an acceptable risk of $5 \%$ against a design flood. The return period for the design flood (in years) is __________ (rounded off to the nearest integer).
The mean rainfall over a catchment has to be estimated. The data for four rain gauges located in and around the catchment is listed in the table. Which one of the following statements is correct:
$$ \begin{array}{|l|c|c|c|c|} \hline \text { Rain gauge station } & \text { P } & \text { Q } & \text { R } & \text { S } \\ \hline \text { Whether located inside the catchment } & \text { Yes } & \text { Yes } & \text { Yes } & \text { No } \\ \hline \text { Thiessen weightage factor } & 0.25 & 0.50 & 0.10 & 0.15 \\ \hline \text { Rainfall (mm) } & 100 & 110 & 100 & 125 \\ \hline \end{array} $$