Answer:
1. According to predominance, water vapor is the most representative greenhouse gas as it accounts for somewhere 30-70% of the greenhouse effect. The atmospheric percentage varies largely, depending on the region and season.
The next most predominant gas is carbon dioxide with 0.0391% of the atmosphere. It causes between 9-26% of the greenhouse effect.
The third is methane with 0.00017% of the atmosphere. It causes between 9-26% of the greenhouse effect. It causes between 4-9% of the greenhouse effect.
2. According to importance for climate change, [tex]CO_{2[/tex] and methane are the primary and secondary gases.
