Hello!
Answer:
Because lifeforms need Oxygen (O2)
Step-by-step explanation:
Lifeforms (anythin living) needs oxygen. The cells on our skin and inside us are living and need oxygen. Belive it or not, cells are living. They need food, water, and O2 to live, which is why we breathe. Without humans and animals plants wouldn't be alive without Carbon Dioxide (Co2), then is the plants die the animals will die, then humans will die aswell.
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