Tiny organisms known as cyanobacteria, or blue-green algae.
When Ag+ is combined with Na2CO3, the substances formed are Ag2CO3 and Na+. In this case, Ag performs single substitution over the element Na to form another set of substances. There are other types of reactions like double displacement, decomposition, etc.
Just an example.. This can affect people because it can cause people to bring umbrellas wear rain coats of it were to rain.
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 .