<span>These are isotopes of carbon and they all contain 6 protons and 6 electrons but each contains a difference number of neutrons - 6, 7, and 8 respectively.
^ This is the answer because an isotope changes the atomic mass, NOT atomic number. That means that the neutrons are changed, not the protons. </span>
No answer is possible until we know the number that belongs after the words "... angular speed of ".
70x3=210 mph... its that easy
The answer is in the attachment
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