A new civil engineer is trying to construct a trapezoidal open channel. The slope and the geometry are restricted by the landscape. Only way to control flow

rate is by changing the Manning Coefficient. Two floor options are available with $n=0\mathrm{.}014$ and $n=0\mathrm{.}025.$ If the interest is to have a low flow rate, which

Manning coefficient should be selected? Why

$0\mathrm{.}025$ because higher the coefficient higher the frictional loss

$0\mathrm{.}025$ because higher the coefficient lower the frictional loss

$0\mathrm{.}014$ because lower the coefficient higher the frictional loss

$0\mathrm{.}014$ because higher the coefficient lower the frictional loss