(Ⅰ)在平面PAB内找一点M,使得直线CM∥平面PBE,并说明理由;
(Ⅱ)若二面角P﹣CD﹣A的大小为45°,求直线PA与平面PCE所成角的正弦值.
“一条条巨龙翻山越岭,为雪域高原送来安康那是一条神奇的天路”,歌词中描绘的铁路线是( )
As long as you keep trying, your dream will certainly .