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Step by steps explanation
Sample Response:
Bacteria are helpful because they produce oxygen, which our bodies need to breathe, and they help us to digest the food we eat. Bacteria are also helpful because they are used in medicine to help us overcome disease. Bacteria are harmful because they can cause tooth decay and illnesses that can be either common or quite serious.
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This is the answer from google!!! hope this helped
The body needs to maintain the amount of oxygen that reaches our cells. If we exercise a lot, our breathing rate increases. More oxygen enables our cells to <span>more quickly respire aerobically, so that our muscles can contract more rapidly.
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The best way to determine the presence of halogens is by adding a silver nitrate solution to the solvent. This is because all halogens, except for fluorine, produce a precipitate with silver nitrate solution.Chlorine produces a white precipitate, bromine produces a pale cream colored precipitate and iodine produces a yellow colored precipitate.
If further testing is required, concentrated sulfuric acid may be added. The sulfuric acid will produce misty fumes with fluorine and chlorine, brown fumes with bromine and purple fumes with iodine.
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