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问题 单项选择题

直升机旋翼桨叶的轨迹通常是（）

A.由于它们的挠性，在桨叶安装前被固定在特殊的夹紧装置上确定的

B.当桨叶在一个规定的转速和总距角度下转动时确定的

C.当桨叶在静止并根据机身中心线处于规定的位置时用三角测量确定的

D.当桨叶平行于机身中心线时，从机身结构到规定的桨叶站位直接测量确定的

答案

参考答案：B

阅读理解

阅读理解，判断“T”误“F”。

      On New Year's Day people eat special foods for good luck.

      In Spain and some Latin American (拉丁美洲) countries, people eat twelve grapes at midnight on

New Year's Eve-one grape for good luck in each month of the new year. 

     Chinese people eat dumplings. Some are made with a coin inside. Everyone tries to find the coin for luck

and money in the New Year. Of course they don't eat the coin.

     Japanese people eat noodles on New Year's Eve and their birthdays. It may bring them good luck and

long life.

( )1. In Spain, people eat a bag of grapes for good luck in the New Year.      

( )2. Chinese people like to eat roast ducks on New Year's Eve.                

( )3. Everyone in China tries to eat the coins in the dumplings in the New Year.

( )4. Japanese people eat noodles on New Year's Eve.                           

( )5. People in different countries eat different foods for good luck.         

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单项选择题

治疗上应首选

A．静注阿托品

B．静点异丙基肾上腺素

C．静点氨茶碱

D．植入心脏起搏器

E．植入埋藏式心脏复律除颤器
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