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在下面括號內列舉的科學家中，對發(fā)現(xiàn)和完善萬有引力定律有貢獻的是
。（安培、牛頓、焦耳、第谷、卡文迪許、麥克斯韋、開普勒、法拉第）

第谷、開普勒、牛頓、卡文迪許解析:
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2．鍛煉身體的方式：ballgames，running，
swimming，．．．
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