A:The strawberry juice is sour and sweet.
B:The strawberry is sour and sweet.
C:The strawberry juice is not sweet. It's sour.
如图,在直线a上求一点O,使它到点M、N的距离最小.
下图中,□和△各代表几?
□+□+△=16
□+△+△=14
□=____
△=____