题干

甲、乙两物体同时同地同方向开始做匀速直线运动,甲的速度大于乙的速度,它们的s﹣t图象是如图所示的a、b、c三条图线中的两条,运动5s 后,、甲、乙间的距离大于2m,则(  )

A:甲的s﹣t图一定为图线a

B:甲的s﹣t图一定为图线b

C:乙的s﹣t图一定为图线c

D:乙的s﹣t图一定为图线a

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A

同类题1

七选五。根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    Choosing the right job is probably one of the most important decisions we have to make in life, and it is frequently one of the hardest decisions we have to make. One important question that you might ask yourself is: “How do I get a good job?” ____ There are people who can answer an insignificant advertisement in the local paper and land the best job in the world; others write to all sorts of places all over the country, and never seem to get a reply at all. Still others believe that the in person, door-to-door approach is by far the best way to get a job; and then there are those who, through no active decision of their own, just seem to be in the right place at the right time. ____ He used to spend a lot of his free time down by the sea watching the tall ships, but never thinking that he might one day sail one of them. His father was a farmer, and being a sailor could never be anything for the boy but an idle dream. One day, on his usual wandering, he heard the captain of the ship complaining that he could not sail because one member of his crew was sick. Without stopping to think, the lad(少年) offered to take his place. ____.

    ____ If the lad had gone home to ponder(考虑)his decision for a week, he may have missed his chance. It is one thing to be offered an opportunity; it is another to take it and use it well. Sometimes we hear stories about people who break all the rules and still seem to land plum jobs(美差). When you go for a job interview or fill out an application, you are expected to say nice things about the company to which you are applying. ____ And within a year this person had become general manger of the company.

A.This story also illustrates the importance of seizing an opportunity when it presents itself.

B.People find jobs in an infinite number of ways.

C.It's almost impossible to find a good job by answering advertisement in newspapers.

D.Take for example the young man who wanted to be a sailor.

E.But there was one person who landed an excellent job by telling the interviewer all the company's faults.

F.He spent the rest of his life happily sailing the ships he had always loved.

G.It is very important to seize an opportunity when it presents itself.

同类题5

                                                                                         Saying no starts small
   “All right then — just one more piece...” Words every girl has said when they are faced with the delicious cheesecake. Of course, many of us know we may eat the whole thing in the end.
    It isn't just girls. Most of us find it hard to say “no” to something attractive. However, scientists now say that willpower is very important to success and a happy life.
    Scientists in different countries have been studying the effects of willpower on people's lives for a long time. The results are similar, according to an article on February 7 in the Guardian, a famous British newspaper.
    In one experiment, scientists told young children that they could either have a marshmallow (圆形软糖) now, or two marshmallows in 15 minutes. Waiting obviously needed more willpower. Scientists then continued studying the children as they grew up. They wanted to see if some children always had stronger willpower. They also wanted to see how having stronger willpower affected their lives.
    Years later, scientists found that the children who had waited for two marshmallows were all healthier, happier and richer adults. Oppositely, the children who had shown weaker willpower at that young age were more likely to be in low-paid jobs, to be overweight, to have social problems.
    But there is hope, Roy F Baumeister, an American social psychology(心理学) professor (教授) told the Guardian. Baumeister says we can train our willpower just like we train our muscles(肌肉). Even a little practice can strengthen(加强) our overall self-control if we do it regularly.
You could start by making yourself stand up straight, speaking in complete sentences, or using a computer mouse with the other hand. Scientists have found that people who manage to change little habits often perform much better in laboratory willpower tests.
    Like muscles, willpower can “get tired”. Don't try to do too many things at the same time, or when you don't have enough energy, for example when you are ill. If you already feel tired, you can try to recharge(恢复) your willpower with a good night's sleep and by eating well.