A good listener takes part in the conversation, ______ ideas and raising questions to keep the talk flowing.
A:having
B:understanding
C:offering
D:supporting
世界上绝大多数动植物都能在我国找到适合生长的地区,主要是国为我国( )
老师将109个香蕉平均分给4个同学,每人分几个?还剩几个?
如图,点B是以AC为直径的圆周上的一点,AB=BC,AC=4,PA=AB,PA⊥平面ABC,点E为PB的中点.
(Ⅰ)求证:平面AEC⊥平面PBC;
(Ⅱ)求直线AE与平面PAC所成角的大小.