题目内容

 If a computer crashes,you will lose the file you _____ on if you don’t save it early enough.

A. are working                     B. work                 C. will work                 D. worked

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People appear to be born to compute. The numerical skills of children develop so early and so inexorably that it is easy to imagine an internal clock of mathematical maturity guiding their growth. Not long after learning to walk and talk, they can set the table with impressive accuracy—one plate, one knife, one spoon, one fork, for each of the five chairs.  Soon they are capable of noting that they have placed five knives, spoons and forks on the table and, a bit later, which this amounts to fifteen pieces of silverware. Having thus mastered addition, they move on to subtraction. It seems almost reasonable to expect that if a child were secluded on a desert island at birth and received seven years later, he or she could enter a second grade mathematics class without any serious problems of intellectual adjustment.

Of course, the truth is not so simple. This century, the work of cognitive psychologists has illuminated the subtle forms of daily learning on which intellectual progress depends. Children were observed as they slowly grasped or, as the case might be bumped into concepts that adults take for granted, as they refused, for instance, to concede that quantity is unchanged as water pours from a short stout glass into a tall thin one.

Psychologists have since demonstrated that young children, asked to count the pencils in a pile, readily report the number of blue or red pencils, but must be coaxed into finding the total. Such studies have suggested that the rudiments of mathematics are mastered gradually, and with effort. They have also suggested that the very concept of abstract numbers--the idea of aloneness, a prerequisite for doing anything more mathematically demanding than setting a table—is itself far from innate.

   1. What's the main idea about this passage?

     A. The use of mathematics in child psychology.

     B. Trends in teaching mathematics to children.

     C. The development of mathematical ability in children.

     D. The fundamental concepts of mathematics that children must learn.

   2. It can be inferred from the passage that children normally learn simple counting——.

     A. soon after they learn to talk 

B. after they reach second grade in school

     C. by looking at the clock

     D. when they begin to be mathematically mature

   3. According to the passage, when small children were asked to count a pile of red and blue pencils they——.

     A. counted the number of pencils of each color

     B. counted only the pencils of their favorite color

     C. guessed at the total number of pencils

     D. subtracted the number of red pencils from the number of blue pencils

   4. What does the word “They” (Para. 3, Line 5) refer?

     A. Children      B. Pencils      C. Mathematicians     D. Studies

 

People appear to be born to compute. The numerical skills of children develop so early and so inexorably that it is easy to imagine an internal clock of mathematical maturity guiding their growth. Not long after learning to walk and talk, they can set the table with impressive accuracy—one plate, one knife, one spoon, one fork, for each of the five chairs.  Soon they are capable of noting that they have placed five knives, spoons and forks on the table and, a bit later, which this amounts to fifteen pieces of silverware. Having thus mastered addition, they move on to subtraction. It seems almost reasonable to expect that if a child were secluded on a desert island at birth and received seven years later, he or she could enter a second grade mathematics class without any serious problems of intellectual adjustment.

Of course, the truth is not so simple. This century, the work of cognitive psychologists has illuminated the subtle forms of daily learning on which intellectual progress depends. Children were observed as they slowly grasped or, as the case might be bumped into concepts that adults take for granted, as they refused, for instance, to concede that quantity is unchanged as water pours from a short stout glass into a tall thin one.

Psychologists have since demonstrated that young children, asked to count the pencils in a pile, readily report the number of blue or red pencils, but must be coaxed into finding the total. Such studies have suggested that the rudiments of mathematics are mastered gradually, and with effort. They have also suggested that the very concept of abstract numbers--the idea of aloneness, a prerequisite for doing anything more mathematically demanding than setting a table—is itself far from innate.

   1. What's the main idea about this passage?

     A. The use of mathematics in child psychology.

     B. Trends in teaching mathematics to children.

     C. The development of mathematical ability in children.

     D. The fundamental concepts of mathematics that children must learn.

   2. It can be inferred from the passage that children normally learn simple counting——.

     A. soon after they learn to talk 

B. after they reach second grade in school

     C. by looking at the clock

     D. when they begin to be mathematically mature

   3. According to the passage, when small children were asked to count a pile of red and blue pencils they——.

     A. counted the number of pencils of each color

     B. counted only the pencils of their favorite color

     C. guessed at the total number of pencils

     D. subtracted the number of red pencils from the number of blue pencils

   4. What does the word “They” (Para. 3, Line 5) refer?

     A. Children      B. Pencils      C. Mathematicians     D. Studies

 


Have you ever walked outside thinking it was one temperature but quickly discovered it felt colder? That is because of the “wind chill” effect.
Wind chill is how cold people and animals feel when they are outside, not the actual temperature on the thermometer(温度计). It is based on how quickly your body loses heat when it is exposed to wind and cold. When the wind is strong, your body quickly loses heat, making the temperature of your skin drop.
When scientists first started calculating wind chill, they used research conducted in 1945 by explorers to Antarctica who measured how quickly water froze outside.
But water freezes faster than exposed skin, so the wind chill index based on that data wasn’t accurate.
In 2001, the US government began to measure wind chill more precisely by testing how quickly people’s skin froze.
Twelve volunteers were placed in a chilled wind tunnel. Equipment was stuck to their faces to measure the heat flow from their cheeks, forehead, nose and chin while they walked three miles per hour on a treadmill(跑步机).
The experiment revealed how quickly exposed skin can be damaged, particularly unprotected areas like your fingers, toes, the tip of your nose and your ear lobes. In fact, 40 percent of your body heat can be lost through your head! Signs you might have frostbite(冻疮) are when the skin turns white or pale and you lose feeling in that area.
The information collected from the volunteers helped scientists work out the math to compute wind chill. It involves wind speed and air temperature.
If, for example, the temperature outside is zero degrees Fahrenheit and the wind is blowing at 15 miles per hour, the wind chill is calculated at 19 degrees below zero. At that wind chill temperature, exposed skin can freeze in 30 minutes.
You can find a calculation table at www.nws.noaa.gov/om/windchill/index.shtml.
Experts advise in cold weather that you wear loose-fitting, lightweight, warm clothing, worn on top of each other. Air caught between the clothes will keep you warm. The best cold-weather coats have head coverings made of woven material that keep out water. So next time the temperature drops and you want to play outside, listen to your parents when they tell you to wrap up warm!
【小题1】 According to the text, wind chill _______.

A.means how fast exposed skin freezes
B.doesn’t affect your head as much as other body parts
C.changes according to the temperature on the thermometer
D.changes from person to person depending on their health
【小题2】 When might a person have frostbite according to the passage?
A.When his skin turns red and he loses feeling in that area.
B.When he is running faster and he is losing strength quickly.
C.When his face is exposed and quickly loses heat even indoors.
D.When his skin turns pale and he has no feeling in that area.
【小题3】 What factors influence wind chill?
A.A person’s body temperature and will speed.
B.Wind speed and a person’s strength.
C.Air temperature and wind speed.
D.The location and air temperature.
【小题4】 What can we conclude from the passage?
A.It was in 1945 that scientists first began to calculate wind chill.
B.Compared with water, people’s exposed skin freezes more slowly.
C.The wind chill index based on Antarctica data is considered a standard.
D.With the development of technology, many previous researches have been proven wrong.

The earth’s most rich resource—water has become one of the most precious resources in the United States as rivers, lakes, and freshwater reservoirs are increasingly exploited for human use. Consequently, using precise farming techniques to refine “irrigation scheduling” is a research area of particular interest to Susan Moran, a researcher with the US department of Agriculture. She explains that in the southwest, irrigation is both difficult and expensive. There, she says, farmers have a tendency to over irrigate, spending both more time and money than is necessary.

“I’m trying to provide new information that could be used by farmers to schedule irrigations to improve their profitability and use less water,” Moran says. “Farmers often look at weather changes and then schedule irrigation based on that information. But if they had better information, they could use scientific models to compute more precisely how much water their crop is using. ”

Rather than guessing their crop’s potential need for water based upon weather changes, farmers can use remote sensors to measure how much water their crop is actually using. This would give them a more accurate measure of how much more water it needs.

Moran believes that if farmers are getting good and timely measurements of plant and air temperature, then they can program when and how much water to give each crop through an irrigation system. No more water would be used than needed, thus saving cost and conserving water.

Moran introduces one study she conducted in Arizona to investigate the use of remote sensing data for scheduling cotton irrigations. Typically, those farmers irrigate ten times per growing season, but evidence showed that some of those farmers could achieve basically the same harvest with only nine irrigations.

“In those cases, one less irrigation saved more than all the cost of remote sensing data,” she states. “Both irrigation and satellite remote sensing data are expensive. But then again many farmers are used to wording together as a group. They are used to sharing. I’m hoping they could do the same with remote sensing data—purchase one scene over a large area to cover many farms, which would further reduce the cost. ”

46. What does Moran think is the problem with farmers?

A. Over-used reservoirs.                          B. Precision farming.

C. Irrigation researches.                           D. Over-irrigation.

47. How can farmers get the new information about their crop?

A. To reschedule irrigation as required.

B. To watch weather changes regularly.

C. To use remote sensors as researchers suggest.

D. To use scientific models since computing is more reliable.

48. What do farmers check upon when they decide how much water each crop needs?

A. Profitability.       B. Remote sensors.     C. The cost.            D. Air temperature.

49. What’s the purpose of Moran introducing the study she carried out in Arizona?

A. To investigate the use of remote sensing data.

B. To support her viewpoint in the previous paragraph.

C. To show how farmers can reap a harvest.

D. To criticize those farmers who used too much water.

50. What is among the best possible ways to help save farmers’ money?

A. Changing irrigation.                             B. Sharing sensing data.

C. Buying one computer.                          D. Extending the farms.

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