Question $\backslash$#$2$b: $[$Marks: $5]$

Compute the EUD value of rainfallusing the Polygon method for a watershed comprising of a perfect square with each side equal to $8$ km $.$ The watershed is located in a relatively flat terrain of Manitoba with North$-$South Orientation. The four rain gauges located in the watershed respectively recorded rain amount equal to $10$ mm at the rain gauge located at Centre of the watershed, and the remaining three rain gauges located in the NW$,$ SW$,$ and SE corners, respectively recorded rain amounts of $\backslash (12\backslash$mathrm$\{$~mm$\},11\backslash$mathrm$\{$~mm$\}\backslash ),$ and $9$ mm $.$