Name an instrument that is used to measure:

Atmospheric pressure.

Name an instrument that is used to measure:

Differences in pressure.

The diagram shows two closed tanks, A and B. Each tank contains gas and is fitted with a manometer to show how the pressure compares with atmospheric pressure outside the tank.

In which tank is the gas pressure greater than atmospheric pressure$?$ Explain how you can tell.

The diagram shows two closed tanks, A and B. Each tank contains gas and is fitted with a manometer to show how the pressure compares with atmospheric pressure outside the tank.

What can you say about the pressure of the gas in the other tank$?$