A narrow, uniform glass tube, closed at one end, constains air which is sealed by a thread of mercury. The tube is placed first horizontally and then vertically with the open end at the top. Which of the following statements is correct?
A. The length of the entrapped air in the horizontal position is less than that in the vertical position B. The length of the entrapped air in the vertical position is less than that in the horizontal position C. The length of the mercury column becomes shorter in the horizontal position than in the vertical position D. The length of the mercury column becomes shorter in the vertical position than in the horizontal position E. The pressure of the entrapped air is atmospheric in both cases.
