A.二氧化碳的含量较多 B.氧气的含量较多 C.水蒸气的含量较多 D.____.
大于1的正整数m的三次幂可“分裂”成若干个连续奇数的和,如23=3+5,33=7+9+11,43=13+15+17+19,…若m3分裂后,其中有一个奇数是103,则m的值是( )
—So it is. It's made _______ grapes, and they can be made _______ many other foods.
如图所示,四棱锥P﹣ABCD的底面ABCD是边长为1的菱形,∠BCD=60°,E是CD的中点,PA⊥底面ABCD,PA=3.
(Ⅰ)证明:平面PBE⊥平面PAB;
(Ⅱ)求二面角A﹣BE﹣P的大小.