All the answers are on the actual periodic table. You should never be told to remember it so I think this is a recourse you are allowed to look at whilst doing your homework lol :) all the answers are written on it hope it helps
D 4 grams
i need to write a couple more character for explanation so there
There are 16electrons in 02
Only answers C and D would make sense in this question. Hope I helped please give brainiest!