Answer:
B
Explanation:
carbon 12 is most useful to humans
<span>Atoms move at different speeds depending on whether they are in liquids or solids </span><span>because the atoms or particles in solids are closely bonded while they are loosely bonded in liquids.
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</span><span>The attractive forces between the particles are so high that they remain in fixed positions. The particles, then, cannot slip over the neighbors particles. They can only vibrate. That is why solids have definite form and volume.</span><span />
<span>That the particles in liquids are loosely bonded means that the attractive forces are less compared with solids. Then the partilces can move and pass each other. They are not in fixed arrangements any more. Yet the particles are attracted to each other, so they have definite volume, although they take the form of the vessel, and they can flow.
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The average atomic mass of the imaginary element : 47.255 amu
<h3>Further explanation </h3>
The elements in nature have several types of isotopes
Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% ..
isotope E-47 47.011 amu, 87.34%
isotope E-48 48.008 amu, 6.895
isotope E-49 50.009 amu, 5.77%
The average atomic mass :

Answer:
atom is the answer I think