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问题 单项选择题

耳可以听到声音的频率范围，通常是（），这个频率范围的声音称可听声。

A.10~1000Hz

B.30~3000Hz

C.20~2000Hz

D.40~4000Hz

答案

参考答案：C

阅读理解

阅读下面短文，掌握其大意，然后根据所给单词的适当形式填空，使短文内容通顺、合理。并将答案完整的填在答题卷上。

In England, people often talk about the weather. Maybe they can experience (经历) four s___1___ in one day. In the morning the weather is warm just like in spring. An hour l___2___ black clouds come and then it rains h___3___. The weather gets a little cold. In the late afternoon the sky will be s___4___, the sun will begin to s___5__, and it will be summer at this time of a day.

In England, people can a__6___ have summer in winter, or have winter in summer. So in winter they can s___7___ in the sea sometimes, and in summer sometimes they should take warm clothes.

When you go to England, you will see that some English people usually take an umbrella or a raincoat w___8_ them in the sunny morning, but you should not l___9___ at them. If you d___10___ take an umbrella or a raincoat, you will regret (后悔) later in the day.
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单项选择题

允许速度不大于120m/h的线路，同向曲线两超高顺坡终点间的夹直线长度在极个别情况下不足25m时，可在直线部分设置不短于（）的相等超高段。

A.10mm

B.15mm

C.20mm

D.25mm
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