Answer:

Explanation:
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In this case, according to the Dalton's law, which explains that the total pressure of a gaseous system equals the sum of the partial pressures of the gases composing, for the gaseous mixture composed by oxygen, nitrogen and carbon dioxide it would be possible to write:

Now, given the pressure of the system and those of oxygen and nitrogen, we calculate that of carbon dioxide as shown below:

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Explanation:
The more reactive element replaces less reactive element during chemical reaction.
Since, potassium is more reactive than beryllium. When potassium reacts with beryllium choride, it replaces beryllium and forms potassium chloride and produces beryllium.
Answer: It's the circulatory system
Explanation:
The law of conservation of matter basically states that matter can’t be created or destroyed, only changed in form, so you can rule out any option that mentions destroying or creating matter. That leaves only option A. Atoms cannot be created or destroyed by chemical reactions.