Which atmosphere was composed primarily of water vapor?

• Primeval Atmosphere
• Evolving Atmospheres 1-4
• Current Atmosphere

Which atmosphere recently cooler and condensed all of the water vapor to create the oceans. 

• Primeval Atmosphere
• Evolving Atmospheres 1-4
• Current Atmosphere

Which atmospheric stage involved scrubbing the CO₂ and SO_x through precipitation?

• Primeval Atmosphere
• Evolving Atmospheres 1-4
• Current Atmosphere

Which gas was introduced by stromatolites and allowed for more complex life to exist on Earth?

• oxygen
• carbon dioxide
• sulfur oxides
• water vapor

This gas was in high concentrations in the early atmosphere, and later condensed to form Earth's oceans. 

• oxygen
• carbon dioxide
• sulfur oxides
• water vapor

This gas was in high concentrations in the developing atmospheres and later dissolved into rainwater, added to the oceans, then settled to the bottom of the ocean. 

• oxygen
• carbon dioxide
• argon
• water vapor

According to the model, how did CO₂ get into the atmosphere?

• evaporation
• condensation
• volcanoes
• sediments

If we wanted to model the introduction of oxygen to this model, where would it take place?

• from the atmosphere to the ocean
• from the ocean to the atmosphere
• from the sediment to the atmosphere
• from the ocean to the sediment

When did stromatolites start added oxygen to the atmosphere?

• Right at the beginning
• Towards the end of the atmosphere evolution
• We're still waiting for it to happen

What is the direct impact of burning fossil fuels?

• Moving CO₂ from the sediment to the atmosphere
• Moving CO₂ from the sediment to the oceans
• Moving CO₂ from the atmosphere to the sediment
• Moving CO₂ from the atmosphere to the oceans