A Venturi tube may be used as a fluid flowmeter (see Fig. 14.19). Taking the difference in pressure as $P_{1}-P_{2}=$ $21.0 \mathrm{kPa}$, find the fluid flow rate in cubic meters per second given that the radius of the outlet tube is $1.00 \mathrm{~cm}$, the radius of the inlet tube is $2.00 \mathrm{~cm}$, and the fluid is gasoline $\left(\rho=700 \mathrm{~kg} / \mathrm{m}^{3}\right)$