The question pertains to hydrostatic lifts. So, assuming you have a lift and you're applying pressure to one side and the other side is rising:
P0 + P1 = P0 + P2 + (rho)gh
Now, when we look at the equation, why is it (rho)gh? I'm thinking it's something like mgh, so to convert it to fluids it would be (rho)Vgh why is this?