At a given location, under normal conditions a river flows with a Manning coefficient of $0\mathrm{.}030$ and a cross section as indicated in the figure below $($a$).$ During flood conditions at this location, the river has a Manning coefficient of $0\mathrm{.}040($because of trees and brush in the floodplain$)$ and a cross section as shown in the figure below $($b$).$ Determine the ratio of the flowrate during flood conditions to that during normal conditions.

$\backslash [$

Q$\_\{$b$\}/$ Q$\_\{$a$\}=$

$\backslash ]$