Answer:
-In an closed-end manometer, the gas pressure is equal to the difference in column heights in the two arms of a U tube.
-In an open-end manometer, the gas pressure pushes on the Hg surface on one arm of the U tube and atmospheric pressure gas pushes on the other.
-The gas pressure is directly related to the height of a column of mercury it produces in a U tube.
Step-by-step explanation:
Manometer is simply an instrument used for measuring the pressure that is acting on a column of liquid.
Now they could either be open ended or closed ended manometers.
However the difference between both of them is that;
Closed - end manometer are those used to measure absolute pressure while open end manometer is used to measure the gauge pressure.
From operation of a closed end manometer, the gas pressure is read from the difference in column heights of the two arms of the U tube being used. While in open end thermometer, the gas pressure will push the mercury surface on one arm of the U tube while the atmospheric pressure gas will push on the other arm.
Lastly, the height of a column of mercury in the U-tube is directly related to the gas pressure.
Thus, the correct options are A, D, E