tolong bantu jawab ya

Ar C = 12, O = 16, N = 14, H = 1

Mr = 12 + 16 + (2x14) + (4x1)
Mr = 60

persen massa Nitrogen
nomor indeks x Ar / Mr x 100%
= 2 x 14 / 60 x 100%
= 28 / 60 x 100%
= 46,6%
jadi jawabannya C