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【单选题】
下列计算式的计算结果(X)几位有效数字?( ) x=[0.3120×48.12×(21.25-16.10)]/0.2845/1000A.
一位
B.
二位
C.
三位
D.
四位
E.
五位
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A.
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B.
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C.
Improper questions are often included in a survey.
D.
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