The axis of a cylindrical vessel is vertical. The vessel is filled with equivalent masses of water and oil. The oil floats on the top of water, and the open surface of the oil is at a height h over the bottom of the vessel. Determine the height, h, when the pressure at the bottom of the water is 11 kPa more than the pressure at the top of the oil? Suppose the oil density is around 875 kg/m3.