You good though mamas got to Scientific and it was growing in general
2/3 is the fraction of the carbon dioxide exhaled by all of the animals that is generated by the reactions of the citric acid cycle, if the gluscose is the sole energy source. So if the glucose is the energy source the fraction of the carbon dioxide is 2/3. The answer in this question is 2/3
Answer:
Nitrogen and oxygen are the most common elements in the atmosphere. They make up almost 99% of the atmosphere by mass. Argon makes up most of the rest of the atmosphere.
Answer: Most of the stars in the universe are main sequence stars — those converting hydrogen into helium via nuclear fusion. A main sequence star may have a mass between a third to eight times that of the sun and eventually burn through the hydrogen in its core. Over its life, the outward pressure of fusion has balanced against the inward pressure of gravity. Once the fusion stops, gravity takes the lead and compresses the star smaller and tighter.
Temperatures increase with the contraction, eventually reaching levels where helium is able to fuse into carbon. Depending on the mass of the star, the helium burning might be gradual or might begin with an explosive flash.
