阅读短文，判断正(T)误(F)。

      Look, this is a picture of a big farm. There are seventy sheep, sixty ducks and one hundred hens. There are

many fresh vegetables, too. The potatoes are big. The tomatoes are red. The carrots and onions are fresh.

( ) 1. The farm is small.

( ) 2. There are many animals and vegetables on the farm.

( ) 3. There are forty ducks.

( ) 4. The potatoes are red.

( ) 5. The onions are fresh.

当蒸发三塔出料浓度偏低时，可适当增加（）的蒸气量。

A、蒸发一塔

B、蒸发二塔

C、蒸发三塔

D、闪蒸