A:produced
B:being produced
C:to be produced
D:having been produced
读某省2003年与2030年(预测)人口年龄结构比较图,完成下面小题。
(Ⅰ)求证:CD⊥AM;
(Ⅱ)若AM=BC=2,求直线AM与平面BDM所成角的正弦值.
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