选择题：如图所示，平面 PAB⊥平面 ABCD，底面 ABCD 是边长为 8 的正方形， ∠APB＝90° ，点 E， F分别是 DC， AP 的中点．（1）证

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题目类型：选择题
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题目内容：

如图所示，平面 PAB⊥平面 ABCD，底面 ABCD 是边长为 8 的正方形， ∠APB＝90° ，点 E， F分别是 DC， AP 的中点．

（1）证明： DF∥平面 PBE；

（2）若 AB＝2PA，求直线 BE 与平面 BDF所成角的正弦值．

A.b＞a＞c

A.b＞a＞c

分类：高考题型：选择题

Whenever Mary reads an interesting story, she can’t keep it to _____ and wants t

Whenever Mary reads an interesting story, she can’t keep it to _____ and wants to share it with her

分类：高考题型：选择题

In order to save the energy, we should ________ lights in time if we don’t need

In order to save the energy, we should ________ lights in time if we don’t need them.

分类：高考题型：选择题

This is one of the highest buildings that ________ in our city recently.

This is one of the highest buildings that ________ in our city recently.

分类：高考题型：选择题

This is one of the best films ________.

This is one of the best films ________.

分类：高考题型：选择题