Some people don't believe that driving more slowly can save lives．But the truth is that driving more slowly can help a person to avoid serious accidents． The above chart shows the distance that it t 题目和参考答案——青夏教育精英家教网—

题目内容

Some people don't believe that driving more slowly can save lives．But the truth is that driving more slowly can help a person to avoid serious accidents．

The above chart（表格） shows the distance that it takes to stop a car at a given speed．The distance is measured in feet．The shaded area（阴影部分） shows the driver's thinking distance．That's the distance it takes for the driver to react to a danger that he sees．The white area shows the car's braking distance．That's the distance it takes for the car to stop once the brakes（闸、刹车） are used．The number at the top of each bar shows the total number of feet that it takes to stop the car

1.According to the chart, what is the total number of feet needed to stop a car that is traveling at 50 miles per hour?

A．55． B．73． C．128． D．183．

2.What is the braking distance for a car that is travelling at 60 miles per hour?

A．66 feet． B．119 feet． C．185 feet． D．251 feet．

3.Which of the following statements about braking and speed is true?

A．The braking distance is what it takes for the driver to react to a danger that he sees．

B．The speed of a car has a direct effect on the distance needed to stop the car．

C．The braking distance increases only when a driver drives faster than 50 miles per hour.

D．Driving slowly can help a person to avoid all accidents

【答案】

1.D2.C3.B

【解析】略

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52. It can be inferred from the passage that ________.

A. nowadays people who want to change their skin colour have to suffer a lot from the damage caused by the chemical treatment

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53. Scientists have done an experiment on a dark-striped zebra fish in order to ________.

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D. find out the ways of changing peopl’s skin colour

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A. they are born light-skinned people

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D. they pay much attention to protecting their skin

55. The writer’s attitude towards the discovery is ________.

A. neutral B. negative C. positive D. indifferent

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The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.

1.. The passage mainly tells us that ________.

A. people can not change their skin colour without any pain

B. the new discovery could lead to search into ways to change skin colour safely

C. pop king Michael Jackson often changed his skin colour as he liked

D. scientists have found out that people’s skin colour is determined by the gene

2.. Scientists have done an experiment on a dark-striped zebra fish in order to ________.

A. find the different genes of humans’

B. prove the humans’ skin colour is determined by the pigment gene

C. find out the reason why the Africans’ skin colour is dark

D. find out the ways of changing peopl’s skin colour

3.. The reason why Europeans are light-skinned is probably that ________.

A. they are born light-skinned people