摘要:7.如图.有两根电线杆AB.CD,已知AB=5m,CD=3m. 现在施工人员在两电线杆底端之间 选一点E,由点E分别向电线杆顶端A.C拉钢索 AE.CE.如果测得∠AEC=90°.且AE=CE. 则BE的长为 米.

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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。(注意:如选E涂AB;选F涂AC;选G涂AD)

  1   People use money to buy food, furniture, books, bicycles and hundreds of other things they need or want. When they work, they usually get paid in money.

Most of the money today is made of metal or paper.   2   One of the first kinds of money was shells.

Shells were not the only things used as money. In China, cloth and knives were used. In the Philippine Islands, rice was used as money for a long time. Elephant tusks, monkey tails and salt were used as money in parts of Africa.

The first metal coins were made in China. They were round and had a square hole in the centre.   3  .

Different countries have used different metals and designs for their money.   4    Sweden and Russia used copper to make their money. Later some countries began to make coins of gold and silver.

But even gold and silver were inconvenient if you had to buy something expensive. Again the Chinese thought of a way to improve money.   5   The first paper money looked more like a note from one person to another than the paper money used today.

Money has had an interesting history from the days of shell money until today.

 

A. The first coins in England were made of tin (锡).

B. But people used to use all kinds of things as money.

C. No one knows for certain when people began to use money.

D. People strung (串连) them together and carried them from place to place.

E. Money, as we know, is all made of paper.

F. They began to use paper money.

G. Today anyone will accept money in exchange for goods and services.

 

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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。注意:涂卡时,如答题卡上没有E、F、G选项,请按如下方式填涂:选E涂AB;选F涂BC;选G涂CD。
Before going outside in the morning, many of us check a window thermometer (温度计) for the temperature. This helps us decide what to wear.    1    We want our food to be a certain coldness in the refrigerator. We want it a certain hotness in the oven. If we don’t feel well, we use a thermometer to see if we have a fever. We keep our rooms a certain warmth in the winter and a certain coolness in the summer.
Not all the thermometers use the same system to measure temperature. We use a system called the Fahrenheit scale. But most other countries use the Centigrade scale.
Both systems use the freezing and boiling points of water as their guide.     2    
The most common kind of thermometer is made with mercury (水银) inside a clear glass tube. As mercury ( or any other liquid ) becomes hot, it expands. As it gets colder, it contracts (收缩) . That is why on hot days the mercury line is high in the glass tube.     3       
First, take a clear glass juice bottle that has a cap; fill the bottle with colored water. Tap a hole in the center of the cap using a hammer and thick nail. Put the cap on the jar. Then stick a plastic straw (吸管) through the nail hole.
     4    
Finally, place a white card on the outside of the bottle and behind the straw. Now you can see the water level easily.
     5     
As the temperature goes down, the water will contract, and the level in the straw will come down. Perhaps you will want to keep a record of the water level in the straw each morning for a week.
A.      We use and depend on thermometers to measure the temperature of many other things in our daily lives.
B.      Thermometers measure temperature, by using materials that change in the same way when they are heated or cooled.
C.      Now that you know this rule you can make a thermometer of your own that will work.
D.      The water will rise in the straw. As the temperature of the air goes up, the water will expand and rise even higher.
E.      They label these in different ways. On the Fahrenheit scale water freezes at 32 degrees and boils at 212 degrees. On the Celsius scale water freezes at 0 degrees and boils at 100 degrees.
F.      Take wax ( you may use an old candle if you have one ) and melt some of it right where the straw is stuck into the cap to seal them together. 
G.      People use thermometers which are made by themselves when travelling around the world.

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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。注意:涂卡时,如答题卡上没有E、F、G选项,请按如下方式填涂:选E涂AB;选F涂AC;选G涂AD。

Watching a sporting event with family and friends under the sun is a great experience in summer.   1.   In the United States, heat exposure led to 8,000 deaths between 1979 and 2003. Luckily, a little prevention can go a long way towards making sure of an enjoyable day.

Know the danger

Heat-related illnesses do not require record-breaking temperatures to occur.   2.  The body’s temperature can reach 106 or 107 degrees Fahrenheit on a 90-degree day, creating a potentially deadly situation. Factors such as age, weight or a medical condition can influence people.

Drink plenty of water

  3.   Sweating is your body’s key way to keep cool, so drink water to stay well hydrated(含水的) before you feel thirsty. A cool beer may sound perfect on a hot day, but drink responsibly. Alcohol stops the body’s cooling system and causes you to go to the bathroom frequently.

   4.   

Wear light-colored and loosely fitting clothing, so air can go around your body and help keep you cool. A hat is a must to help you keep cool, since your head contains many blood vessels(血管), and sun block(防晒乳) is always a good idea.

Take action

What should you do if you are suffering from the heat while watching your favorite event?

Get up and go. It is a simple piece of advice, but could make the difference between a quick recovery and something more severe that requires medical attention. The ideal thing is to move yourself from the position you’re in to an area that is a little cooler.  5.  

A. Dress for the occasion

B. Weather-related causes

C. In hot weather, it is essential to stay hydrated.

D. You may miss a little of the action, but it beats missing a lot.

E. But when you add sun exposure to the crowds, the results can be deadly.

F. It is also important to take advantage of services the equipment provides.

G. Temperatures between 80 and 90 degrees Fahrenheit can be dangerous.

 

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