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general knowledge Online Quiz - 5118
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Multiple Choice
How much Carbon dioxide (CO2) is in Earth's atmosphere today?
- 10% or greater
- less than 1/10th of 1%
- 2% to 10%
- 1%
general knowledge Online Quiz - 5118
Learn at your own pace with hints and detailed explanations
How much Carbon dioxide (CO2) is in Earth's atmosphere today?