/~\ The correct answer is:
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<em><u>Hydrogen is a chemical and is </u></em><em><u>found in the sun and most of the stars, </u></em><em><u>and the</u></em><em><u> planet Jupiter</u></em><em><u> is composed mostly of hydrogen. On Earth,</u></em><em><u> </u></em><em><u>hydrogen is found in the</u></em><em><u> greatest quantities as water.</u></em>
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I hope this helps! /~\
What they have in common is that they both have the same number of atoms. Hope this helps. :)
The correct answer for, An element with the smallest anionic (negative-ionic) radius would be found on the periodic table in, is <span>Group 17, Period 2.</span>