Question [3] Freshwater and seawater flowing in parallel horizontal pipelines are connected to each other by a double U-tube manometer, as shown in the figure below. Pmercury = 13600 kg/m³ - Pfreshwater = 1000 kg/m³ - Pseawater = 1035 kg/m³ - Pair = 1.2 kg/m³ a) Determine the pressure difference between the two pipelines. [25 points] b) Can the air column be ignored in the analysis?

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