题干

火车在长直的轨道上匀速行驶,门窗紧闭的车厢内有一人向上跳起,发现仍落回到原处,这是因为(     )

A:人跳起后,车厢内空气给他向前的力,带着他随火车一起向前运动

B:人跳起的瞬间,车厢的地板给人一个向前的力,推动他随火车一起运动

C:人跳起后,车继续前进,所以人落下必然偏后一些,只是由于时间很短,偏后的距离不易观察出来

D:人跳起后直到落地,在水平方向上人和车具有相同的速度

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D

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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.