某研究者在做儿童生长发育研究时，测量了一批儿童身高的数据，欲估计总体均数，其总体均数

欲测量一个电流表的内阻，根据以下要求来选择器材和设计电路：

1无论怎样调节变阻器，电流表都不会超量程

2有尽可能高的测量精度，并能测得多组数据。

现备有器材如下：

A.待测电流表A₁（量程3mA，内阻约为50Ω）

B.电压表 V  (量程3V，内阻未知）

C.电流表A₂  （量程15mA，内阻等于10Ω）

D.保护电阻R=120Ω  

E.直流电源E（电动势2V，内阻忽略）

F.滑动变阻器（总阻值10Ω，额定电流0.5 A）

G.开关、导线若干代码

小题1:在以上提供的器材中，除A、E、F、G以外，还应选择           、          

小题2:试在方框中画出符合下述要求的实验电路图

已知X^＋、Y^2＋、Z^－、W^2－四种离子均具有相同的电子层结构。下列关于X、Y、Z、W四种元素的描述，正确的是 (    )

A．原子半径：X＞Y＞Z＞W

B．原子序数：Y＞X＞Z＞W

C．原子最外层电子数：Y＞X＞Z＞W

D．金属性：X<Y，还原性：W^2－＞Z^－

L4损伤平面的关键肌为（）

A.长伸肌

B.屈髋肌（髂腰肌）

C.伸膝肌（股四头肌）

D.足背伸肌（胫骨前肌）

E.足跖屈肌（腓肠肌、比目鱼肌）

在识别和确认顾客要求时，要实现顾客满意的关键是( )。

A．获得顾客满意度
B．获得顾客理解
C．获得顾客支持并提供满意信息
D．获得顾客要求及其信息数据

In a democratic society citizens are encouraged to form their own opinions on candidates for public office, taxes, constitutional amendments, environmental concerns, foreign policy, and other issues. The opinions held by any population are shaped and manipulated by several factors: individual circumstances, the mass media, special-interest groups, and opinion leaders.

Wealthy people tend to think differently on social issues from poor people. Factory workers probably do not share the same views as white-collar, nonunion workers. Women employed outside their homes sometimes have perspectives different from those of full-time homemakers. In these and other ways individual status shapes one’s view of current events.

The mass media, especially television, are powerful influences on the way people think and act. Government officials note how mail from the public tends to "follow the headlines. " Whatever is featured in newspapers and magazines and on television attracts enough attention that people begin to inform themselves and to express opinions.

The mass media have also created larger audiences for government and a wider range of public issues than existed before. Prior to television and the national editions of newspapers, issues and candidates tended to remain localized. In Great Britain and West Germany, for example, elections to the national legislatures were usually viewed by voters as local contests. Today’s elections are seen as struggles between party leaders and programs. In the United States radio and television have been beneficial to the presidency. Since the days of Franklin D. Roosevelt and his "fireside chats," presidents have appealed directly to a national audience over the heads of Congress to advocate their programs.

Special-interest groups spend vast sums annually trying to influence public opinion. Public utilities, for instance, tried to sway public opinion in favor of nuclear power plants. Opposed to them were citizens’ organizations that lobbied to halt the use of nuclear power. During the 1960s the American Medical Association conducted an unsuccessful advertising campaign designed to prevent the passage of Medicare.

Opinion leaders are usually such prominent public figures as politicians, show-business personalities, and celebrity athletes. The opinions of these individuals, whether informed and intelligent or not, carry weight with some segments of the population. Some individuals, such as Nobel Prize winners, are suddenly thrust into public view by the media. By quickly reaching a large audience, their views gain a hearing and are perhaps influential in shaping views on complex issues.

Which of the following is true according to the passage（）

A. TV programs have a p influence on governmental policy

B. Chats on televisions are chief means for running for presidency

C. More and more people show interest in politics because of TV

D. Before the use of TV, people showed little interest in politics