- 问题详情:如图所示,四面体SABC中,,∠SBA=45°,∠SBC=60°,M为AB的中点.则BC与平面SAB的夹角为()A.30° B.60°C.90° D.75°【回答】B知识点:空间中的向量与立体几何题型:选择题...
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