钓鱼岛自古就是我国固有领土.又称钓鱼台.钓鱼台群岛.钓鱼台列岛.位置在距温州市约356km.福州市约385 km.基隆市约190 km.若我国某海监船为维护我国对钓鱼岛主权.从温州出发去钓鱼岛巡航.到达钓鱼岛时航行了480 km.则下列说法中不正确的是 A．该海监船位移是480 km.路程356kmB．该海监船位移是356 km.路程4 题目和参考答案——青夏教育精英家教网—

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钓鱼岛(The Diaoyu Islands)自古就是我国固有领土，又称钓鱼台、钓鱼台群岛、钓鱼台列岛，位置在距温州市约356km、福州市约385 km、基隆市约190 km。若我国某海监船为维护我国对钓鱼岛主权，从温州出发去钓鱼岛巡航，到达钓鱼岛时航行了480 km。则下列说法中不正确的是

A．该海监船位移是480 km，路程356km

B．该海监船位移是356 km，路程480 km

C．该海监船在海上航行时，确定其位置时可以将该海监船看成质点

D．若知道此次航行时间可求出此次航行的近似平均速度

试题分析：位移表示由初位置指向末位置的有向线段，路程表示实际运动轨迹的长度，故路程大于等于位移大小，所以该海监船位移是356 km，路程480 km，A错误，B正确，
该海监船在海上航行时，确定其位置时其大小和形状可以忽略故能看做质点，C正确，
平均速度等于位移与时间的比值，故给出时间即可求出平均速度，D正确，
故选A
点评：平均速度等于位移与时间的比值，平均速率等于路程与时间的比值，路程大于等于位移大小，当做单向直线运动时，位移大小等于路程

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A．该海监船位移是480 km，路程356km

B．该海监船位移是356 km，路程480 km

C．该海监船在海上航行时，确定其位置时可以将该海监船看成质点

D．若知道此次航行时间可求出此次航行的近似平均速度

The days of the hunter are almost over in India. This is partly because there is practically nothing left to kill, and partly because some steps have been taken mainly by banning tiger-shooting to protect those animals which still survive.

Some people say that man is naturally a hunter. I disagree with this view. Surely our earliest forefathers, who at first possessed no weapons, spent their time digging for roots, and were no doubt themselves often hunted by meat-eating animals.

I believe the main reason why the modern hunter kills is that he thinks people will admire his courage in overpowering dangerous animals. Of course, there are some who truly believe that the killing is not really the important thing, and that the chief pleasure lies in the joy of the hunt and the beauty of the wild countryside. There are also those for whom hunting in fact offers a chance to prove themselves and risk death by design; these men go out after dangerous animals like tigers, even if they say they only do it to rid the countryside of a threat. I can respect reasons like these, but they are clearly different from the need to strengthen your high opinion of yourself.

The greatest big-game hunters expressed in their writings something of these finer motives. One of them wrote:

“You must properly respect what you are after and shoot it clearly and on the animal’s own territory (领地).You must fix forever in your mind all the wonders of that particular day. This is better than letting him grow a few years older to be attacked and wounded by his own son and eventually eaten, half alive, by other animals. Hunting is not a cruel and senseless killing — not if you respect the thing you kill, not if you kill to enrich your memories, not if you kill to feed your people.”

I can understand such beliefs, and can compare these hunters with those who hunted lions with spears and bravely caught them by the tail. But this is very different from many tiger-shoots I have seen, in which modern weapons were used. The so-called hunters fired from tall trees or from the backs of trained elephants. Such methods made tigers seem no more dangerous than rabbits.

There is little hunting in India now partly because ________.

A. it is dangerous to hunt there B. hunting is already out of date

C. hunters want to protect animals D. there are few animals left to hunt

The author thinks modern hunters kill mainly ________.

A. to make the countryside safe B. to earn people’s admiration

C. to gain power and influence D. to improve their health

What do we learn about the big-game hunters?

A. They hunt old animals. B. They mistreat animals.

C. They hunt for food. D. They hunt for money.

What is the author’s view on the tiger-shoots he has seen?

A. Modern hunters lack the courage to hunt face-to-face.

B. Modern hunters should use more advanced weapons.

C. Modern hunters like to hunt rabbits instead of tigers.

D. Modern hunters should put their safety first.

钓鱼岛（The Diaoyu Islands）自古就是我国固有领土，又称钓鱼台、钓鱼台群岛、钓鱼台列岛，位置在距温州市约356km、福州市约385km、基隆市约190km．若我国某海监船为维护我国对钓鱼岛主权，从温州出发去钓鱼岛巡航，到达钓鱼岛时航行了480km．则下列说法中不正确的是（）
A．该海监船位移是480 km，路程356km
B．该海监船位移是356 km，路程480 km
C．该海监船在海上航行时，确定其位置时可以将该海监船看成质点
D．若知道此次航行时间可求出此次航行的近似平均速度

Are you sometimes a little tired and sleepy in the early afternoon? Many people feel this way after lunch. They may think that eating lunch is the cause of the sleepiness. Or, in summer, they may think it is the heat. However, the real reason lies inside their bodies. At that time – about eight hours after you wake up – your body temperature goes down. This is what makes you slow down and feel sleepy. Scientists have tested sleep habits in experiments where there was no night or day. The people in these experiments almost always followed a similar sleeping pattern. They slept for one long period and then for one short period about eight hours later.

In many parts of the world, people take naps in the middle of the day. This is especially true in warmer climates, where the heat makes work difficult in the early afternoon. Researchers are now saying that naps are good for everyone in any climate. A daily nap gives one a more rested body and mind and therefore is good for health in general. In countries where naps are traditional, people often suffer less from problem such as heart disease.

Many working people, unfortunately, have no time to take naps. Though doctors may advise taking naps, employers do not allow it! If you do have the chance, however, here are a few tips about making the most of your nap. Remember that the best time to take a nap is about eight hours after you get up. A short sleep too late in the day may only make you feel more tired and sleepy afterward. This can slao happen if you sleep for too long. If you do not have enough time, try a short nap – even ten minutes of sleep can be helpful.

45．Why do people feel sleepy in the early afternoon according to the text?

A．They eat too much for lunch.

B．They sleep too little at night.

C．Their body temperature becomes lower.

D．The weather becomes a lot warmer.

46．If you get up at 6:30 am, what is the best time for you to take a nap?

A．About 12:30 pm. B．About 1:30 pm.

C．About 2:30 pm D．About 3:30 pm

47．What would be the best title for the text?

A．Just for a Rest B．All for a Nap

C．A Special Sleep Pattern. D．Taking Naps in Warmer Climate.

C 46—50：CB

There _____ a lot of coal mines in the south, but many of them have been closed or are _____ be closed.

A. use to having; about to B. used to be; to

C. use to having; going to D. used to be; supposed to

The shopkeeper did not want to sell for he thought was not enough.

A．where B．how C．what D．which

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