글 수정하기
글쓴이
E-mail
Homepage
글제목
글
Do you play any instruments? <a href=" http://www.devista.com/?hindgra-mg.pdf#articles ">hindgra / sildenafil tablets reviews</a> Two years ago, he and a team from the universities of Bristol and Oxford examined some rocks from Greenland which had their origins in a part of the Earth's mantle that was insulated from meteorite activity for a crucial period some 600 million years. The team did not look at the gold content of the 4.4-billion-year-old rocks, but at tungsten. Tungsten has some similarities to gold but exists in different forms or isotopes, and this provides scientists with more historical information.
비밀번호
(수정과 삭제시 필요!! )