Physics - Fluid Question with Solution | TestHub

Initially, the outside oil pressure is
$$P_{\mathrm{out}}=P_0+{\rho }_{o}g(15)$$
At the hole, the inside hydrostatic pressure is
$$P_{\mathrm{in}}=P_0+{\rho }_{o}g(5)+{\rho }_{w}g(10)$$
Bernoulli gives
$$\frac{1}{2}{\rho }_w{v}^2=({\rho }_w-{\rho }_o)g(10)$$
$$v=\sqrt{40}m/s\approx 6.3m/s$$
The flow slows as the water level falls. It stops when the inside and outside pressures agree:
$${\rho }_{w}gh={\rho }_{o}g(10)$$
$$h=\frac{{\rho }_o}{{\rho }_w}(10)=8\mathrm{m}$$
Hence A, B and C are correct.