原子结构的第三壳层最多容纳电子数是()
A.2个
B.8个
C.18个
D.32个
E.50个
参考答案:C
—How did you like TV play "Heroes"?
—Oh, it was wonderful. It's one of best TV plays I've ever seen. [ ]
A. a ; the
B. the ; a
C. the ; /
D. the ; the
口咽通气管仅限______和______的昏迷病人使用。