3、A、B是一条电场线上的两个点，一带负电的微粒仅在电场力作用下以一定初速度从A点沿电场线运动到B点，其速度-时间图像如图甲所示。则这一电场可能是图乙中的　　　　　　 　　　　　　　　　　　　　　　　　　　　

2、取两个粗细、材料完全相同的长导线，用其中一根绕成如图(a)所示的螺线管，当该螺线管中通以电流强度为I的电流时，测得螺线管内中部的磁感应强度大小为B，若将另一根长导线对折后绕成如图(b)所示的螺线管，并通以电流强度也为I的电流时，则在螺线管内中部的磁感应强度大小为

A．0　　　 B．0.5B　　　

C．B　　 　　　　 D．2 B

1、磁体之间的相互作用是通过磁场发生的。对磁场认识正确的是

A．磁感线有可能出现相交的情况

B．磁感线总是由N极出发指向S极

C．某点磁场的方向与放在该点小磁针静止时N极所指方向一致

D．若在某区域内通电导线不受磁场力的作用，则该区域的磁感应强度一定为零

74．What does the underlined sentence in paragraph 4 mean?

　　　 A．Our college experiences prove that those surveys are incorrect.

　　　 B．The surveys may remind us of our beautiful college experiences.

　　　 C．The surveys should all be reexamined according to our college experiences.

　　　 D．Our college experiences may make us misunderstand the results of the surveys.

73．Which of the following is one of some observers’ opinions?

　　　 A．The students expect so much that they are not satisfied with the hard college life.

　　　 B．The economic situation is so discouraging that the youth have to attend college.

　　　 C．Colleges should improve because of so much campus unhappiness.

　　　 D．Colleges provide more chances of good jobs than anywhere else.

72．According to the passage all the following statements are true EXCEPT that　　　 .

　　　 A．about half of the high school graduates continue their studies in colleges.

　　　 B．college graduates are believed to be able to earn more money.

　　　 C．administrators often encourage college students to drop out.

　　　 D．more and more young people are found unfit for college.

71．What does the passage mainly talk about?

　　　 A．Internet culture　　　　　　　　　　　　　　　　　　 B．Electronic mail message.

　　　 C．Fahlman’s creation.　　　　　　　　　　　　　　　 D．Online smiley face.

E

　　　 The case for college has been accepted without question for more than a generation. All high school graduates ought to go, because college will help them earn more money, become“better”people, and learn to be more responsible citizens than those who don’t go.

　　　 But college has never been able to work its magic for everyone. And now that close to half our high school graduates are attending, those who don’t fit the pattern are becoming more and more, and more obvious. College graduates are selling shoes and driving taxis; college students get in the way of each other’s experiments and write false letters of recommendation in the competition for admission to graduate school. Others find not interest in their studies, and drop out-often encouraged by college administrators.

Some observers say the fault is with the young people themselves-they are spoiled and they are expecting too much. But that is a condemnaiton(谴责)of the students as a whole, and does not explain all campus unhappiness. Others blame the state of the world, and they are partly right. We’ve been told that young people have to go to college because our economy cannot take in an army of untrained eighteen-year-olds. But disappointed graduates are learning that it can no longer take in an army of trained twenty-two-year-olds, either.

　　　 Some adventuresome educators and campus watchers have openly begun to suggest that college may not be the best, the proper, the only place for every young person after the completion of high school. We may have been looking at all those surveys upside down, it seems, and thinking of the rosy glow of our own remembered college experiences. Perhaps college does not make people intelligent(clever)，ambitious, happy, liberal, or quick to learn things-maybe it is just the other way round, and intelligent, ambitious, happy, liberal, quick-learning people are only the ones who have been attracted to college in the first place. And perhaps all those successful college graduates would have been successful whether they had gone to college or not. This is heresy(异端邪说)to those of us who have been brought up to believe that if a little schooling is good, more has to be much better. But opposite evidence is beginning to mount up.

70．The purpose of　 Fahlman in typing the first smiley face was　　　 .

　　　 A．to explain to others that he didn’t take his message seriously.

　　　 B．to fill all the world’s communication channels with smiley faces.

　　　 C．to make money out of telecom companies and online merchants.

　　　 D．to show his happy feelings and to help to define Internet culture.

69．What do the underlined words this information in paragraph 3 refer to?

　　　 A．the body language.　　　　　　　　　　　　　　　 B．the suggestion of marking posts

　　　 C．the tone of voice　　　　　　　　　　　　　　　　　 D．the humors behind the words