题目内容:
A high negative ion count is likely to be found
A.near a pond with a water pump.
B.close to a slow-flowing river.
C.high in some barren mountains.
D.by a rotating water sprinkler.
参考答案:
A high negative ion count is likely to be found
A.near a pond with a water pump.
B.close to a slow-flowing river.
C.high in some barren mountains.
D.by a rotating water sprinkler.