Answer
$0.24N$
Work Step by Step
We can find the required force as follows:
$\frac{\Delta m}{\Delta t}=[(\frac{31in}{9h})(\frac{0.0254m}{in})(\frac{1h}{3600s})](1m^2(\frac{1000Kg}{m^3}))$
$\implies \frac{\Delta m}{\Delta t}=0.024\frac{Kg}{s}$
Now $F=\frac{\Delta m}{\Delta t}(v)$
We plug in the known values to obtain:
$F=(0.024)(10)=0.24N$
