爆炸销毁场地应距国家铁路干线和独立的居民点保持在()以上。
A.2km
B.3km
C.5km
参考答案:A
Can you explain _____ most deserts are located near the west coast of the continents? [ ]
A. why is it that
B. why it is that
C. how it is that
D. how is it that
在三大功能营养中,只有蛋白质能为人体提供的元素是()
A.氮
B.碳
C.氢
D.氧