On this page all p tags are getting styling from the internal style sheet. They are set to 150% font size and they are set to have green text. The OL is also part of the red but is not red because the selector is p.red instead of just .red .
This is paragraph 1. It is not a member of a class
This is paragraph 2. It is a member of the red class. Only the red class is set to have red text. It overrides the green text.
This is paragraph 3. It has the ID of blue, and is part of the red class. It is blue because ID is overriding the green text and the red class.