题干

(2009·泰州模拟)“月球勘探者号”空间探测器运用高科技手段对月球进行了近距离勘探,在月球重力分布、磁场分布及元素测定方面取得了新的成果.月球上的磁场极其微弱,通过探测器拍摄电子在月球磁场中的运动轨迹,可分析月球磁场的强弱分布情况,如图是探测器通过月球表面①、②、③、④四个位置时,拍摄到的电子运动轨迹照片(尺寸比例相同),设电子速率相同,且与磁场方向垂直,则可知磁场从强到弱的位置排列正确的是   (  )

A:①②③④

B:①④②③

C:④③②①

D:③④②①

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A

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People on a college campus were more likely to give money to the March of Dimes if they were asked for a donation by a disabled woman in a wheelchair than if asked by a nondisabled woman. In another 1 , subway riders in New York saw a man carrying a stick stumble(绊脚) and fall to the floor. Sometimes the victim had a large red birthmark on his2; sometimes he did not. In this situation, the victim was more likely to 3 aid if his face was spotless than if he had an unattractive birthmark. In 4 these and other research findings, two themes are 5 : we are more willing to help people we like for some reason and people we think6assistance.

In some situations, those who are physically attractive are more likely to receive aid. 7 , in a field study researchers placed a completed application to graduate school in a telephone box at the airport. The application was ready to be 8 , but had apparently been "lost". The photo attached to the application was sometimes that of a very 9 person and sometimes that of a less attractive person. The measure of helping was whether the individual who found the envelope actually mailed it or not. Results showed that people were more likely to 10 the application if the person in the photo was physically attractive.

The degree of 11 between the potential helper and the person in need is also important. For example, people are more likely to help a stranger who is from the same country rather than a foreigner. In one study, shoppers on a busy street in Scotland were more likely to help a person wearing a(n) 12 T-shirt than a person wearing a T-shirt printed with offensive words.

Whether a person receives help depends in part on the "worth" of the case. For example, shoppers in a supermarket were more likely to give someone. 13 to buy milk rather than to buy cookies, probably because milk is thought more essential for 14 than cookies. Passengers on a New York subway were more likely to help a man who fell to the ground if he appeared to be 15 rather than drunk.