$5\mathrm{.}3\mathrm{.}20$ WP Water is pumped from the tank shown in Fig. P$5\mathrm{.}3\mathrm{.}20$a$.$ The head loss is known to be $1\mathrm{.}2\frac{V^2}{2}g,$ where $V$ is the average velocity in the pipe. According to the pump manufacturer, the relationship between the pump head and the flowrate is as shown in Fig. P$5$:$3\mathrm{.}20$b: $h_p=20-2000Q^2,$ where $h_p$ is in meters and $Q$ is in $\frac{m^3}{s}.$ Determine the flowrate, $Q.$

$($a$)$

$($D$)$

FIGURE P$5\mathrm{.}3\mathrm{.}20$