将铜片放入0.1mol/LFeCl3溶液中,反应一定时间后取出铜片,溶液中c(Fe3+):c(Fe2+)=2:3,则Cu2+与Fe3+的物质的量之比为( )
A:3:2
B:4:13
C:3:4
D:3:5
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— I'm reading the book ______you lent me last week.
已知分式 A=xx−4+yy−4