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问题 选择题

已知R1：R2=2：1，则它们（　　）

A．串联时的电流之比为2：1

B．串联时的功率之比为1：1

C．并联时的电流之比为2：1

D．并联时的电压之比为1：1

答案

A、串联电路中，电流相等，电流之比1：1．不符合题意．

B、串联电路中，

P1
P2
=
I2R1
I2R2
=
R1
R2
=
2
1
．不符合题意．

C、并联电路中，

I1 
I2 
=
U
R1
U
R2
=
R2
R1
=
1
2
．不符合题意．

D、并联电路中，电压相等，电压之比为1：1．符合题意．

故选D．

阅读理解

Have you ever heard the saying “If you want a friend, be one”? If you want to make friends with others, you should be friendly to them at first.

Here is how one ① /new teacher made friends/ with the pupils in her class on the first day of school. As the bell rang, the teacher smiled at each pupil. Then she said in a quiet voice, “Good morning. How nice it is to have all of you in my class this year. I’d like to know each of you. I am sure we will enjoy working together.” ② Her voice was sweet and her look was friendly, so everyone felt happy.

She told the pupils her name and wrote it on the blackboard. Then she told them some of the things she liked to do and she was hoping to do with them during the year. ③ Then she said to the boys and girls, “Now you know my name and the things I like and I want to know your names and the things you like. ”

Could you make friends by doing the same as this teacher did?

One way of getting to know girls and boys in your class is to find out more about them. ④People often make friends with those who have the same hobbies. You play the same games and go on journeys together. It is a good way to make friends.

小题1:根据①处的注音写出英语单词。

小题2:根据②处的划线句子在下面句子中的每个空白处填入一个适当的词（首字母已给出）。

Everyone felt happy b_______ o________ her sweet voice and her friendly look.

小题3:1）在③处的划线部分中找出哪个词的最后一个音可以失去爆破。

2）在③处的划线部分中找出两个可以连读的词。

小题4:将④处的划线句子翻译成汉语。

小题5:从文中找出一句能概括本文主旨大意的句子。
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单项选择题

某高层钢筋混凝土框架结构，抗震等级为一级，混凝土强度等级为C30，钢筋采用 (fyv=270N/mm2)。框架梁h0=340mm，其局部配筋如图所示，根据梁端截面底面和顶面纵向钢筋截面面积的比值和截面的受压区高度，试判断关于梁端纵向受力钢筋的配置，并提出其中何项是正确的配置（）

A.Asl=3Ф25As2=2Ф25

B.Asl=3Ф25As2=3Ф20

C.Asl=As2=3Ф22

D.前三项均非正确配置
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