问题
选择题
—Why are you making so much noise?
—I just can't help . [ ]
A. so
B. that
C. this
D. it
答案
答案：D
搜题请搜索小程序“爱下问搜题”
—Why are you making so much noise?
—I just can't help . [ ]
A. so
B. that
C. this
D. it
答案：D
内的平均速度是
，则物体在整个过程中的平均速度是 [ ]
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v