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 .
add up the mass of protons and neutrons
Answer:
So, 10 mole of water will weigh (18x10) = 180g.
Answer:The mass numbr is 22
Explanation:
Mass number=number of protons+ number of neutrons....which is 10+12=22
I believe that it most likely would be D.