Do you know Bernoulli's?

A fixed cylindrical tank with a large cross sectional area is filled with two liquids of density $P$ and $2P$ in equal volume, as shown in the diagram below. A small hole of area $\sqrt{6}\text{ cm}^2$ is made at height $15\text{ m}$ from the bottom, and we assume that the gravity is $g=10\text{ m/s}^2$ .

Find
(a) the speed of efflux (in $\text{SI}$ units)
(b) the cross sectional area (in $\text{ cm}^2$ ) of the stream of the liquid just before it hits the ground.

Provide your answer as the sum of the values found in (a) and (b).