C-12 is a real carbon atom that present in atmosphere naturally very much higher than c-14 because this is a carbon isotope that was formed artificially in nuclear reactions. And thanks for new year wish di, now my wishes for public practicals and exams, all the best!, i am impressed of ur approach and i'm likely to have friendship with u, hmm... r u in facebook? if u r at fb and find my fb id at sredhar str (shark) give friend request to me, then we will meet there bye