A:30°
B:45°
C:60°
D:90°
若对自然界中的水进行净化处理,其中净化程度最高的方法是
在下列现象中,可以证明地球自转的是( )
is her hair? It is black.
A:Would you mind my smoking here?
B: ______. Look at the sign. It says" No smoking."