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is a life-sustaining, odorless gas in the air.
is a waste product of respiration

User Fantasy Fang
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2 Answers

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21 votes

Answer: 1. Oxygen

2. Carbon Dioxide

Step-by-step explanation:

User HSBP
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12 votes

Answer:

Carbon dioxide

Step-by-step explanation:

Carbon dioxide is produced by cellular respiration and is a life sustaining gas for organisms that use photosynthesis

User Yuriy Tumakha
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