PV=nRT, that is high school, I learn it in high school.

 There is gas, liquid, solid diagram.

If you are joining in one of those professional tests, you probably need to except all the textbook basic diagram.

That is one of them. 

You learn about temperature, you learn about mp, bp

Melting point

Boiling point.

It is a standard procedure how you define gas, liquid, or solid.

You will see in Ice, water, Vapor! 

Steam ! 

Steam train we used to have 16th century before 18th industrial evolution and you sign 1789 French independence, to say

When is America 200 years history? Constitution of America, Bill of Rights!