Answer:
Some (most) has two tails.You can see the tails when the comets go near the sun.There are two types of comet tails,dust and gas ion. Comet tails can be over 600,000 miles (1 million km) long.Because the comet dust particles are so small, they are pushed away from the Sun into a long tail.They are made of ices, such as water, carbon dioxide, ammonia and methane, mixed with dust.There are so much more to discover about comets (which I might not know).
Hope that was helpful.Thank you!!!
My educated guess should be the 3rd one
Answer:

Explanation:
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In this case, since this acid-base neutralization is performed in a 1:2 mole ratio of acid to base as the former is a diprotic acid (two hydrogen ions in the molecule), we can write the following equation:

In such a way, we can solve for the molarity of the acid, given the molarity and concentration of the NaOH base and the volume of the acid:

Thus, we plug in the given data to obtain:

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Answer:
B. An element whose particles are molecules.
Explanation:
B her parents arranged for her to get married in paris