The inclined manometer shown below is used to measure the pressure difference in a pipeline carrying oil (sg = 0.91). the manometer tube is inclined at an angle of 30° to the horizontal, and the pressure taps on the pipe are 5 in. apart. the manometer fluid is mercury (sg of 13.6). (a) derive a formula for h, in terms of l and θ. (b) if the manometer reading (l) is 3 in. what is the pressure drop in the pipe in pa, and in psi?