$(7)$ Listed below are the annual maximum instantaneous discharge values

recorded for Thompson River near Spences Bridge $($WSC $08$LF$051).$ The

drainage area of Thompson River at this gauging station is approximately

$54900k{m}^2.$ Using the Gumbel paper provided, construct a graph to

illustrate the relation between the magnitude and frequency of flood events.

Source: Environment Canada, Historical Streamflow Summary, $1990.$

$(3)$ Determine the magnitude of the mean annual flood $(Q_{2\mathrm{.}33}),$ bankfull

discharge $(Q_{1\mathrm{.}58})$ and the $100-$year flood $(Q_{100}).$

$(2)$ All discharge measurements include measurement errors. The error

associated with measurements of discharge is commonly assessed as $+-5$

$\%$ of the actual discharge value. Calculate the error term of the smallest

and largest discharge values in the data series and then the corresponding

range $($i$.$e$.$ lower and upper limits$)$ in which the actual discharge may be

found.