ca is an abbreviation of the Latin word 'circa' = about, so ca 300 refers to about 300 years ago.
From about 300 million years ago to 180 million years ago.
it was 300 years ago
300 years ago - roughly the same time as the industrial revolution escalated.
1712
300 years ago
about 10,000 years ago
In millions .
300 million years ago The Appalachian Mountain Range is estimated to be formed 300 millions years ago, when Pangaea was breaking off into Laurasia and converged further into Africa and North America.
there were invented 300 years ago
about 300 years ago, they had swords called kattana.
1707.