Answer
1200 Pa.
Work Step by Step
Use Poiseuille’s equation, 10-9, to find the pressure difference.
$$Q=\frac{\pi R^4 (P_1-P_2)}{8 \eta \mathcal{l}}$$
$$ P_1-P_2=\frac{8Q \eta \mathcal{l}}{\pi R^4}$$
Convert the flow rate Q to $6.5 \times10^{-4}\;m^3/s$.
$$ P_1-P_2=\frac{8(6.5 \times10^{-4}\;m^3/s) (0.2\;Pa \cdot s) (1600\;m)}{\pi (0.145\;m)^4}$$
$$ P_1-P_2=1198\;Pa\approx1200\;Pa$$