The answer is C) catalyst speed up reactions and activation energy
Answer:

Explanation:
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In this case, since the mass percentages in a compound which is wanted to know the molecular formula, can be assumed to be the masses, we first need to compute the moles they have in the formula unit:

Next, we divide each moles by the fewest ones (3.73 mol) in order to find the subscript in the empirical formula first:

Then, the empirical formula is BH2N whose molar mass is 26.83 g/mol, so the ratio of molecular to empirical is 80.50/26.83=3; therefore, the molecular formula is three times the empirical one:

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A. hex- Normally with 6, the prefix is hex-. For example a polygon having 6 sides is known as hexagon.
Answer:
99.86%
Explanation:
The sun contains 99.86% of the mass in the solar system. It is a HUGE star and it is the brightest star too. the other .14% is usually the planets and the galaxy's.