— Can you play the piano? ( )
—________.
A:No, I don't
B:No, I'm not
C:No, I can't
往含Br﹣和Cl﹣的稀溶液中滴入AgNO3溶液,沉淀的质量与加入AgNO3溶液体积的关系如图所示.则原溶液中c(Br﹣)/c(Cl﹣)的比值约为( )