Q41:
Scientists have dated sharp-edged flakes of stone found in the fine-grained sediments of a dry riverbed in the Afar region of Ethiopia to between 2.52 and 2.60 million years ago, pushing back by more than 150,000 years the earliest date when it is known that humans made stone tools.
选A或E?我在两个不同的版本上看的答案不同.
欢迎光临 ChaseDream (https://forum.chasedream.com/) | Powered by Discuz! X3.3 |