The figure shows a simple barometer which consists of a U-tube ... ...

  The figure shows a simple barometer which consists of a U-tube with one end closed (1) and the other end open to the atmosphere (2). image The liquid in the barometer is mercury, with a density of ρHg = 13.6 g/cm3. The height of mercury in column 1 is h1, and the cross-sectional area is A1. The height of mercury in column 2 is h2, and the cross-sectional area is A2. Volume 1 is filled with an unknown gas. What is the best expression for the pressure in volume 1?
(A) image
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in 10. Fluids