List any three human activities which would lead to an increase in the carbon dioxide content of air.

Three Human Activities That Increase Carbon Dioxide (CO₂) in the Air

1. Burning of Fossil Fuels – The combustion of coal, oil, and natural gas in industries, vehicles, and power plants releases large amounts of carbon dioxide into the atmosphere.
2. Deforestation – Cutting down trees reduces the Earth’s ability to absorb CO₂ through photosynthesis, leading to an increase in atmospheric CO₂ levels.
3. Industrial Processes – Factories and manufacturing units release CO₂ as a byproduct of activities like cement production, metal refining, and chemical processing.