Answer: Carbon Dioxide, Nitrogen, Argon, and oxygen.
Explanation: Earth's atmosphere is 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide with very small percentages of other elements.
<h2>Answer</h2>
The parasympathetic neurotransmitter at target organs is <u>acetylcholine</u><u>.</u>
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I don’t knows if it has options, but Evolution
<span>The Left-sided Problem of the heart involves the lack of enough supply of oxygen induced blood and the blood which is unable to reach the heart goes to lungs causing breath issues. Another issue with this problem is that left side of the heart pumps blood into the body, so when it fails, less blood will be pumped into the arteries.</span>
A. Citric acid cycle (Krebs cycle)