在C语言中，形参的缺省存储类是（）。A.auto B.register C.stat

小明同学为了探究一组材料的隔音性能（材料：泡沫塑料板、玻璃、木板、ep]硬纸板）设计并做了一个实验，他把这些材料做成盒子，先把闹钟放入其中一个盒子当中，然后从听到最响的声音位置开始，慢慢远离声源，测得听不到指针走动声音时的距离．

比较各种情况下这段距离的大小就可以比较不同材料的隔声性能．进行实验后收集到的数据为：

材料	听不到闹钟指针走动声音时的实际距离/m
泡沫塑料板	0.3
玻璃	0.6
木板	0.4
硬纸板	0.5

（1）你认为该实验中，应注意哪些问题？（说出两个）______，______．

（2）按隔音效果好坏依次排列：______、______、______、______．

（3）总结好的隔音材料的共同特点之一是：______．

如图所示，在oxyz坐标系所在的空间中，可能存在着匀强电场E或匀强磁场B，也可能两者都存在．现有一质量为m、电荷量为q的正点电荷沿z轴正方向射入此空间，发现它做速度为v₀的匀速直线运动．若不计此点电荷的重力，则下列关于电场E和磁场B的分布情况中有可能的是（　　）

A．E≠0、B=0，且E沿z轴正方向

B．E=0、B≠0，且B沿z轴正方向或负方向

C．E≠0，B≠0，B沿x轴正方向，E沿y轴负方向

D．E≠0，B≠0，B方向可在平行于xoy平面的任何方向且E方向平行于xoy平面并与B的方向垂直

This is a dangerous world we live in．The number of murders goes up every year, people are dying of cancer, more people contract HIV, more teens are using drugs, etc．You know this because you have heard all the statistics on the news and in the paper． But do you really have an accurate idea what they mean? The numbers are growing up, but how do they compare to the growth in population? Are more cases of these diseases being reported because of better testing techniques, or are the diseases more common? The fact is that without knowing the background statistics mean very little．

This growing trend of reporting only part of the information is becoming dangerous．For example, several years ago a high school student reported the dangers of the chemical known as dihydrogen monoxide．This chemical, found in most cancerous tumors（肿瘤）, is often found in the blood of people drunk on alcohol, and causes complete physical and mental dependence for those who take the chemical even once．After reading his report, more than 75% of his Advanced Placement Chemistry class voted to forbid this dangerous chemical! Every one of the above statements is true, yet this chemical is necessary to all life on earth．The students made the mistake because they voted knowing only a few statements and statistics, rather than the chemical’s full background．

The point of this article is that one should be aware of what is and is not being said．When one finds a new fact or number, one should try to consider other important information before forming an opinion with only half-truths．Always remember that the author is trying to convince you of his or her own view, and will leave out information that is different to his view．For example, look again at the statistics that suggest skiing is safe．Only 32 people may die each year when skiing, while 897 die from lightning strikes, but which is really the most dangerous? If you think about it, you realize far fewer people go skiing each year than the number of people who are in danger of a lightning strike．When you think about it, skiing is more dangerous than you might at first think when looking at statistics．If we teenagers are to be left in this world, we had better be able to think critically, and form our own views, rather than be easily persuaded by another’s．To be warned is to be prepared．

小题1:In the first paragraph, what problem does the writer want to warn us?

A．We are now living in a dangerous world．

B．We get a lot of false statistics from the media．

C．Statistics alone without full background doesn’t give us an accurate pictures of things．

D．There are around us more and more murders, diseases, etc．小题2:Why does the writer use the example in the second paragraph?

A．To argue that high school students are easily persuaded．

B．To show the danger of reporting only part of the information．

C．To prove what is necessary to us might be dangerous．

D．To warn us of the harmful substance around us．小题3:Relative information is often left out because__________．

A．Relative information is not that important．

B．too much information will make readers feel confused．

C．the author is trying to show what he or she says is true．

D．readers are not able to analyze so much information at once．小题4:What can we learn from the passage?

A．We should learn to think critically and look at problems from all sides．

B．Some measures must be taken to protect our dangerous world．

C．The growing trend of reporting only half-truths is getting out of control．

D．Teenagers ought to improve their ability of telling right from wrong．

人大代表在选举的基础上产生。根据选举法规定，中华人民共和国年满十八周岁的公民，不分民族、种族、性别、职业、家庭出身、宗教信仰、教育程度、财产状况和居住期限，都有选举权和被选举权；但是依照法律被剥夺政治权利的人没有选举权和被选举权。这段话的主要意思是( )

A．年满十八岁的公民都有选举权和被选举权

B．被剥夺政治权利的人没有选举权和被选举权

C．人大代表在选举的基础上产生

D．选举权的行使受到政治法律等方面的限制

解决方案呈现结束时，呈现者为什么要总结重点?