托盘天平调零后,在左盘衬纸上放置氧化铜粉末,右盘衬纸上放置1

托盘天平调零后,在左盘衬纸上放置氧化铜粉末,右盘衬纸上放置1个5 g砝码,游码标尺示数如下,此时天平平衡。则被称量的氧化铜质量为
A.7.7 gB. 8.3 gC.3.3 gD.2.7 g

答案

A解析:

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