【单选题】
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①
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②
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③
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④
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【单选题】
在Excel中，当前工作表的B1：C5单元格区域已经填入数值型数据，如果要计算这10个单元格的平均值并把结果保存在D1单元格中，则要在D1单元格中输入____。
①
=COUNT(B1:C5)
②
=AVERAGE(B1:C5)
③
=MAX(B1:C5)
④
=SUM(B1:C5)