Is silver nonrenewable or renewable

It is non renewable, as there is very little (hence it is rare and so expensive)

GL!

Ithink its d.stratum

They contributed many things, but here are some examples:

1) democracy - democracy as a political system was first implemented in ancient athens
2) some advances in mathematics - such as the pythagoras' law
3) the script - the roman script was adopted from ancient greek.