A:x> 433
B:x<2或x> 433
C:x<2
D:2<x< 433
7+9=____
—Hurry up. The bus is coming.
—Wait a minute. Don't cross the street _______ the traffic lights are green.
下列有关静脉血的叙述中,错误的是( )
读青藏地区图,回答下列问题: