Answer:
Is there like a graph or model for this question?
Explanation:
All of the above.
The main greenhouse gases are: methane, carbon dioxide, chlorofluorocarbons, ozone, nitrous oxides and water vapor.
If the nitrogenous base is made of two rings that means it's a purine(adenine, guanine), if it's made of one ring that means it's a pyrimidine(cytosine,thymine, uracil).