客户证件信息维护交易为（）交易，主要用于对客户证件信息进行维护。

如图为氧元素的原子结构示意图：

（1）氧元素的原子核内质子数为       ，最外层电子数为      。

（2）在点燃条件下，红磷可以与氧气发生反应，其反应的化学方程式为                   。

某物理兴趣小组要精确测量一只电流表G（量程为1mA、内阻约为100Ω）的内阻。实验室中可供选择的器材有：

电流表A₁：量程为3mA，内阻约为200Ω；

电流表A₂：量程为0.6A，内阻约为0.1Ω；

定值电阻R₁：阻值为10Ω；

定值电阻R₂：阻值为60Ω；

滑动变阻器R₃：最大电阻20Ω，额定电流1.5A；

直流电源：电动势1.5V，内阻0.5Ω；

开关，导线若干。

（1）为了精确测量电流表G的内阻，你认为该小组同学应选择的电流表为__________、定值电阻为__________。（填写器材的符号）

（2）在方框中画出你设计的实验电路图。

（3）按照你设计的电路进行实验，测得电流表A的示数为I₁，电流表G的示数为I₂，则电流表G的内阻的表达式为r_g=__________。

阅读理解。

     American Youth Millions of words have been written about young people in the United States. There are

reasons for this great interest in the ideas, feelings, and actions of youth.

     Today there are about seven million Americans in colleges and universities. Young persons under twenty-

five make up nearly half of the American population. Many of these will soon be in charge of the nation.

Naturally their ideas are important to everyone in the country, and it is necessary for older people to understand

what they think and feel.

     College students today have strong opinions about right and wrong. They are deeply interested in making a

better life for all people, especially for those who have not been given a fair chance before now. They see much

that is wrong in the lives of their parents. It is hard for them to see what is right and good in the older ways. As

a result, there is often trouble in American families. Your country may be meeting such problems, too.

1. The meaning of the underlined phrase "make up" is _____.

A. 编造

B. 构成

C. 补偿

D. 化妆

2. Which of the statements would the writer probably agree?

A. It is unfortunate that so much attention is being paid to young people in the United States.

B. Older people should try to understand the thoughts and feelings of youth.

C. Many problems today are caused by parents who do not control their children.

D. The young people of today are mainly interested in enjoying life.

3. The last sentence says, "Your country may be meeting such problems, too." The phrase "such problems" 

    refers most directly to _____.

A. crime caused by the use of drugs

B. the newer sexual freedom of youth

C. young people's dislike of hard work

D. disagreements between young people and their parents

25000KVA矿热电炉的电极压放程序？

下列河流有凌汛的是（）

A、密西西比河

B、叶尼塞河

C、尼罗河

D、伏尔加河