Mass number is the number of protons and neutrons in an atom, and it tells us about the mass of the atom in amu, or atomic mass units. Atomic mass is the average mass of all the isotopes of a certain type. It is a weighted average that takes into account the abundances of all of the different isotopes
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Answer:
Enzymes
Explanation:
Enzymes are proteins that can act as catalysts in the body.
They are called hydrocarbons
Because all matter has density and since air has density then air is matter and plus EVERYTHING is made of matter
