已知两圆柱正交(轴线垂直相交),如图所示,三视图中相贯线的已知投影有几个。
A. 1个
B. 2个
C. 3个
D. 无法分析
查看答案
两圆柱面相交产生的相贯线形式有?
A. 外表面和外表面相贯
B. 内表面和内表面相贯
C. 内表面和外表面相贯
D. 不能确定
The next-door neighbours are so ___________that we have stopped trying to talk to them. (friend)
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