1. The problem statement, all variables and given/known data 2. Relevant equations 3. The attempt at a solution Hello, In this problem, and with problems dealing with pressures in manometers in general, I'm wondering if to calculate the pressure at any given point, you just look at what is above that point. For example, at Point C, there is 12 feet of mercury and 12.65 feet of oil on top of it, as well as the atmosphere. Does that mean that to find the pressure at point C, I just add in the ρgh from the 12 ft of mercury and the other ρgh from the oil as well as the P_atm? For the pressure at point A, I know that its filled with water up to that point, so the water must be counteracting that 12 feet of mercury and 12.65 feet of oil, but where do I include the actual water pressure itself in here?