xiaokaoy
'c. 635–542 Ma' - Does "c." mean "circa" or "about"? What does "Ma" in the phrase mean? Is it the same as "BC"?
2012年6月13日 01:21
解答 · 2
xiaokaoy, The abbreviation for circa is c. or ca. It means the same as "about" or "approximately". "Ma" is an abbreviation for "million years ago". c. 635–542 Ma = approximately 635 to 542 million years ago.
2012年6月13日
還沒找到你要的答案嗎?
寫下你的問題,讓母語者來幫助你!