Whoops. Basically, they want the gauge pressure of the bottom liquid.
In the answer to the problem, when calculating the gauge pressure of the bottom liquid, they also subtract off the 3atm pressure from the upper liquid. The book's answer is 5, which comes from: 8 - (1 +3).
You're telling...
Homework Statement
A large cylinder is filled with an equal volume of two immiscible fluids. A balloon is submerged in the first fluid; the gauge pressure in the balloon at the deepest point in the first fluid is found to be 3 atm. Next, the balloon is lowered all the way to the bottom of the...