越多越好!
就只要两大内容..全英文!
人气:253 ℃ 时间:2020-05-22 17:58:37
解答
Copper is a reddish metal with a face-centered cubic crystalline structure.It is malleable,ductile,and an extremely good conductor of both heat and electricity.It is softer than iron but harder than z...
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