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You Asked ➤ Which of the following processes begins when a star enters the main sequence?
↴ OUR CHOICES ↴
A: Nuclear fission
B: Nuclear fusion
C: Condensation of a nebula
D: Appearance of a supernova
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Answer ➤ B: Nuclear fusion
Explanation: When a star begins the process of being created, it is hot and dense. Really hot and dense! It begins to start fusing with helium which is the start of its main sequence called nuclear fusion.
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<em>- Qamar </em>
Continents move and the earth's surface changes over time
The population of red beetles will more likely to decrease over time, meanwhile the green beetles may increase. This is because in a new environment, red beetles are more likely to be found by predators, and green ones can camouflage themselves, so the red ones will be eaten, while the green ones stay unbothered so that the rate will even increase.
In a dehydration synthesis reaction, water is always formed as a by-product of the reaction.
<h3>What is a dehydration synthesis reaction?</h3>
A dehydration reaction in chemistry is a chemical process in which the reacting molecule or ion loses water. The opposite of a hydration reaction, dehydration reactions are frequent processes.
Dehydration synthesis is a chemical reaction that joins two smaller molecules by eliminating atoms from each of them. Organic compounds can be further divided into aliphatic and aromatic compounds based on the structure of hydrocarbons. The generation of new compounds with changes in atom bonding can occur in a variety of chemical processes involving organic molecules.
To learn more about dehydration synthesis reaction with the help of given link:
brainly.com/question/3156803
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Answer:
b
Explanation:
breath in oxygen, breathe out co2.
plants breathe in c02, breathe out oxygen
