________ people visit the Great Wall every day.
A:Hundred of
B:Hundreds of
C:Two thousands of
D:Thousand of
已知正实数a,b,且a+b=1,则2a+4b的最小值为 ( )
下图为北半球示意图,若箭头表示洋流动力方向,则该洋流是( )
台湾省东部濒临的是( )