http://en.wikipedia.org/wiki/Archimedes'_principle http://www.mamabaodian.com/mamabaodian/articleinfo.php?id=2700
曹冲称象与Archimedes' principle
stradem (2013-02-10 20:46:14) 评论 (0)http://en.wikipedia.org/wiki/Archimedes'_principle http://www.mamabaodian.com/mamabaodian/articleinfo.php?id=2700