读“地球的西半球图”，回答以下问题。
pH小于5.6的雨水称为____，这种雨水对生物有极大的危害．
只读一个“零”的数是（ ）
—Where are you going for your winter holiday?
—I’m going to visit Kunming. It is ______ too hot _______ too cold.
