The three cylinders shown are identical. The piston in each cylinder is free to slide up and down without friction. The pistons are identical. Each piston is shown in its equilibrium position, and the top of each piston is exposed to the atmosphere.

Rank the cylinders based on the pressure of the gas confined inside.

1. 1>2>3
2. 3>2>1
3. 1=2=3
4. There is not enough information given to answer the question.