Answer:
They contain of atoms
Explanation:
That's because atomic weights or masses of each atom of each element are proportional to each other, the same number of atoms of each element will give masses that are also proportional to each other. If you start with 20 oxygen atoms, you will need 40 hydrogen atoms to make the water and you will get 20 molecules of water.
Answer:
I think it the carbon 14 which is a half life of 5730 because in 4.5billion years ago I don't think any human being existed on earth I'm not sure I hope that I helped you and good luck .
