1. The problem statement, all variables and given/known data My teache recently assigned this problem but its nothing like the atmospheric problems we've done in class. Any suggestions on where to start? The cross section of the tube of a mercury barometer is 1 square centimeter, and when the barometric height is 760 millimeters, 6 centimeters of the upper end of the tube is empty. When a bubble of air is passed up into the tube it is found that the mercury surface in the tube drops 2 centimeters. Calculate the volume of the bubble of air at atmospheric pressure. 2. Relevant equations 3. The attempt at a solution The volume of mercury would be V=ha = (760)(1) = 760 but that is as far as I've gotten.