题干
–Hello, May I speak to Tony, please?-Certainly.____.
A：I'd love to
B：The line is busy
C：I am afraid not
D：Hold on, please.
答案(点此获取答案解析）
D
–Hello, May I speak to Tony, please?-Certainly.____.
A：I'd love to
B：The line is busy
C：I am afraid not
D：Hold on, please.
来计算平均数，用这种方法计算平均数又叫做
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