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问题 单项选择题

医用低频电流的频率范围是多少Hz

A．0～100Hz
B．0～1000Hz
C．0～10000Hz
D．0～100000Hz
E．0～1000000Hz

答案

参考答案：B

解析：低频电流的频率范围是0～1000Hz。

单项选择题 A1型题

L型细菌缺失哪一种结构（）。

A.细胞质

B.细胞膜

C.细胞核质

D.细胞壁

E.核糖体
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听力题

阅读下面短文，然后根据括号内所给汉语的意思写出单词的正确形式（每空一词）。

Henry works in a factory. He comes from a poor family and was in school for only four years. He has to do more work, but he’s paid 1      (较少的). He likes to watch football matches very much and 2       (花费)a lot of time on it.

One evening there was a big football match. He 3      (借)some money from his friend and hurried there. There were a lot of people there. And all the tickets were 4      (卖)out. He 5     (感到)sorry for it. He saw a pole(电线杆)outside the playground and climbed it up quickly. A policeman came and said, “It’s dangerous to stay on it. Come down!”

“Wait a minute, please!” Henry said and just at the moment the policeman 6        (听到) cheers in the playground and asked in a hurry, “Which team has kicked a goal?” “Ours!” “Wonderful! You can stay there but take care,” the policeman said 7        (高兴地) and left. When the match would soon be over, he came back again and asked, “Who’s 8      (赢)?” “Theirs, 3-2.” “Come down,” the policeman said 9        (生气地). “Such a match that we shouldn’t10         (观看) it.”

Henry had to come down. But soon they heard cheers again. The policeman said in a hurry, “Climb up quickly and see who’s kicked a goal!”
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