Answer:
i will think c-n=3 to NM=2
Oxidation numbers is the right answer
4) would be your correct answer

<em>Chemists use the mole unit to represent 6.022 × 10 23 things, whether the things are atoms of elements or molecules of compounds. This number, called Avogadro's number, is important because this number of atoms or molecules has the same mass in grams as one atom or molecule has in atomic mass units. </em>
hope helpful~
E=mc (square) E= mass times capacity squared