食盐是重要的调味品,精盐是由粗盐提纯而来,在提纯过程中通常不需要的操作是
A:蒸发
B:吸附
C:过滤
D:溶解
一 have you been to London?
— Three times.
如图,已知A4,0,B0,4,从点P2,0射出的光线经直线AB反射后再射到直线OB上,最后经直线OB反射又回到P点,则光线所经过的路程是( )
(2016•恩施州)-- Where is your father?
-- I don't know, but he _______ the car when I left just now.