Answer the following question given this paragraph: 

The atmospheric pressure is converted from kPa to mmHg in order to match units with the table. The sum of the pressures of the hydrogen and the water vapor is equal to the atmospheric pressure. The pressure of the hydrogen is found by subtraction. Then, the volume of the gas at STP can be calculated by using the combined gas law.


Q: The sum of the pressures of the hydrogen and the water vapor is equal to what?

 Choices:

- moon pressure

- adjacent pressure

- precipitation pressure

- atmospheric pressure

A:
atmospheric pressure
