选择题：9.(单选题)垂直于H面，平行于V面的平面称为（）。(本题3.0分)A.正垂面 B.正平面

题目内容：

9.(单选题)垂直于H面，平行于V面的平面称为（）。(本题3.0分)
A.正垂面
B.正平面
C.水平面

参考答案：

18.(单选题)延长旅游点生命周期的根本办法,是( )(本题3.0分)A.市场宣传B.降价出售C.连

18.(单选题)延长旅游点生命周期的根本办法,是( )(本题3.0分)A.市场宣传B.降价出售C.连续发展D.延长成熟期

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