$4.)$ Water at $90C$ is flowing through $1^{\text{'}\text{'}}$ heat exchanger tube $(18Ga{)}^{**1}$ at a Reynolds number of $71591.[$See footnote below. You can find the density and viscosity information from Table A$\mathrm{.}4\mathrm{.}1$ Physical Properties of Water at the Saturation Pressure on Page $8.]$

What is the flow rate in liters$/$second$?$