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速度与机械运动

> 下列几种估测中比较符合实际情况的是 A.教室内天花板离地面的高度约为6 m B.家里一盏40W的灯正常工作时的电流是1 A C.中学生正常步行的速度为5 m/s D.学校升旗时演奏中华人民共和国国歌用时约50 s

问题：

发布时间：2024-09-07

下列几种估测中比较符合实际情况的是

A.教室内天花板离地面的高度约为6 m
B.家里一盏40W的灯正常工作时的电流是1 A
C.中学生正常步行的速度为5 m/s
D.学校升旗时演奏中华人民共和国国歌用时约50 s

参考答案：

提问用户：O3***xNF

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