An inclined tube manometer with a reservoir is used to measure the pressure gradient in a large pipe carrying oil (sg = 0.91). the pipe is inclined at an angle of 60° to the horizontal, and flow is uphill. the manometer tube is inclined at an angle of 20° to the horizontal, and the pressure taps on the pipe are 5 inches apart. the manometer reservoir diameter is eight times as large as the manometer tube diameter, and the manometer fluid is water. if the manometer reading (l) is 3 inches and the displacement of the interface in the reservoir is neglected, what is the pressure drop in the pipe in (a) psi; (b) pa; (c) in. h2o? what is the percentage error introduced by neglecting the change in elevation of the interface in the reservoir?