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This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. Theres a Native American site in Ohio that appeared to be a fort. But recent discoveries by archaeologists at the University of Cincinnati show thats n
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(WA) One reason oceanographers analyze the sediment on the ocean floor is to see how long-terms changes in Earth's temperature have affected the depth of the ocean. By analyzing the remains of sea animals in old layers of ocean sediment, oceanograph
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It seemed like a good ideabecause rivers and ponds in Bangladesh were contaminated with bacteria, Bangladeshis switched to wells. But soon after, in the early 80s, researchers realized those wells were harming Bangladeshis with a new poisonarsenic. T
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Lake Sediment Could Better Date Ancient Finds Radiocarbon dating is the best-known and most widely used method to determine the age of organic material, such as bone or wood or plant matter. All such material contains radioactive carbon atoms, known
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首先，我建议同学们不要上完辅导班就去参加考试。虽有趁热打铁之说，但是我相信绝大部分同学在上课期间已经把大部分的精力用于听讲和记笔记了，回家之后基本上就直奔安乐窝了。能够
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