A:PCl5
B:BCl3
C:CCl4
D:NH3
已知 sinπ4-x=513,0<x<π4,则 1cosπ4+x的值为( )
Teachers' Day in China is 10th September while South Korea's Teachers' Day is May.
读下图,甲、乙、丙三地的气候类型都是( )