题目内容

阅读理解。
     Even plants can run a fever, especially when they're under attack by insects or disease.
But unlike humans, plants can have their temperature taken from 3,000 feet away-straight up.
A decade ago, adapting the infrared (红外线) scanning technology developed for military
purposes and other satellites, physicist Stephen Paley came up with a quick way to take the
temperature of crops to determine which ones are under stress. The goal was to let farmers
precisely target pesticide (杀虫剂) spraying rather than rain poison on a whole field, which
invariably includes plants that don't have pest problems.
     Even better, Paley's Remote Scanning Services Company could detect crop problems
before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an
infrared scanner measured the heat emitted by crops. The data were transformed into a
color-coded map showing where plants were running "fevers". Farmers could then spot-spray,
using 50 to 70 percent less pesticide than they otherwise would.
     The bad news is that Paley's company closed down in l984, after only three years. Farmers
resisted the new technology and long-term backers were hard to find. But with the renewed
concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get
back into operation. Agriculture experts have no doubt the technology works. "This technique
can be used on 75 percent of agricultural land in the United States", says George Oerther of
Texas A & M. Ray Jackson, who recently retired from the Department of Agriculture, thinks
remote infrared crop scanning could be adopted by the end of the decade. But only if Paley  
finds the financial backing which he failed to obtain 10 years ago.
1. Plants will emit an increased amount of heat when they are ________.
A. sprayed with pesticides        
B. facing an infrared scanner  
C. in poor physical condition      
D. exposed to excessive sun rays
2. In order to apply pesticide spraying precisely, we can use infrared scanning to       .
A. estimate the damage to the crops      
B. draw a color-coded map            
C. measure the size of the affected area    
D. locate the problem area
3. Farmers can save a considerable amount of pesticide by        .
A. resorting to spot-spraying          
B. consulting infrared scanning experts  
C. transforming poisoned rain         
D. detecting crop problems at an early date
4. The application of infrared scanning technology to agriculture met with some difficulties due to       .
A. the lack of official support      
B. its high cost              
C. the lack of financial support      
D. its failure to help increase production
5. Infrared scanning technology may be brought back into operation because of       .
A. the desire of farmers to improve the quality of their produce
B. growing concern about the excessive use of pesticides on crops
C. the forceful promotion by the Department of Agriculture
D. full support from agricultural experts
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阅读理解。
     Even plants can run a fever, especially when they're under attack by insects or disease. But unlike human,
plants can have their temperature taken from 3, 000 feet away straight up. A decade ago, adopting the infrared
(红外线) scanning technology developed for military purposes and other satellites, physicist Stephen Paley
came up with a quick way to take the temperature of crops to determine which ones are under stress. The
goal was to let farmers precisely aim at pesticide (杀虫剂) spraying rather than rain poison on a whole field,
which was sure to include plants that don't have pest (害虫) problems.   
     Even better, Paley's Remote Scanning Services Company could detect crop problems before they became
visible to the eye. Mounted on a plane flown at 3, 000 feet at night, an infrared scanner measured the heat
given out by crops. The data were transformed into a color-coded map showing where plants were running
"fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.   
     The bad news is that Paley's company closed down in 1984, after only three years. Farmers resisted the
new technology and long-term backers were hard to find. But with the increasing concern about pesticides
on produce, and improvement in infrared scanning, Paley hopes to get back into operation. Agriculture experts
have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the
United States," says George Oerther of Texas A & M. Ray Jackson, who recently retired from the Department
of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if
Paley finds the financial backing which he failed to obtain 10 years ago.
1. Plants will give out an increased amount of heat when they are _____.
[     ]
A. sprayed with pesticides  
B. facing an infrared scanner
C. in poor physical condition  
D. exposed to extreme sun rays
2. In order to apply pesticide spraying precisely, we can use infrared scanning to _____.
[     ]
A. estimate the damage to the crops  
B. measure the size of the affected area
C. draw a color-coded map  
D. locate the problem area
3. Farmers can save a considerable amount of pesticide by _____.
[     ]
A. adopting spot-spraying  
B. consulting infrared scanning experts
C. transforming poisoned rain  
D. detecting crop problems at an early stage
4. The application of infrared scanning technology to agriculture met with some difficulties of _____.
[     ]
A. the lack of official support  
B. its high cost
C. the lack of financial support 
D. its failure to help increase production
5. Infrared scanning technology may be brought back into operation because of _____.   
[     ]
A. the desire of farmers to improve the quality of their produce   
B. growing concern about the over use of pesticides on crops   
C. the forceful promotion by the Department of Agriculture
D. full support from agricultural experts
阅读理解。
     Even when you're extremely busy, you aren't using your time with 100% efficiency. There are
gaps in everyone's schedule where they aren't doing anything important. Even if your schedule has
no gaps, there is probably lots of time where you aren't working as fast or as effectively as you
possibly could.
     Why aren't you completely efficient? It's because time isn't the limiting factor. If it were the
limiting factor, people could work non-stop without breaks or any unproductive distractions(消遣).
Instead, people, even those who are highly productive, need to take breaks, occasionally
procrastinate(拖延) and slow down on tasks throughout the day.
     The real and most important limiting factor for productivity is your energy levels to pay attention.
Energy levels limit your productivity because when you're tired, you can have ample time and still
not get everything done. Your attention ability is also limited, because even if there are a million
things that need to be done, you can only focus on one or two at a time.
     You might not be able to insert another 4-5 hours into your schedule without making some
sacrifices(牺牲). But even extremely busy people can add an hour or two into their schedule
without cancelling anything. The reason it's hard to "find time" isn't a lack of time. It's because
you don't have enough energy left to focus on something else that needs to fit into your day.
     I first suspected time wasn't the real problem during an extremely busy period in my life over
a year ago. I was insanely busy, but at that time I still exercised regularly. I had daily to-do lists
with over twenty items, and I still found time to exercise. However, after a few weeks off, due to
illness, I stopped exercising. I was not busy by any standards, in fact, my schedule was incredibly
light. Despite this free time, I found it hard to find time to exercise. It seemed to get pushed later
and later into my schedule until it was gone. How can I explain this odd experience? I believe y
ou have known it.
1. If someone can't work with 100% efficiency, the most important limiting factor is ________.
A. a schedule without gaps           
B. breaks and distractions
C .the limited time                      
D. the limited energy
2. According to paragraph 4, everyone, including the extremely busy people, can ___________.
A. work without any rest                 
B. focus on many things at a time
C. find some more time in a day            
D.do some exercise regularly
3. After a few weeks off, what was the change of the writer's life?
A. He had a longer daily to-do lists with over twenty items.
B. He stopped doing exercise because of the lack of energy.
C. He found it hard to find time to exercise because he was busier.
D. He pushed most of the things later and later in his schedule.
4. The writer gives the example of himself in the last paragraph in order to ___________.
A. prove what the real limiting factor is  
B. show us how busily he needs to work
C. explain how important a healthy body is  
D. tell us what an odd experience he has
5. What is the best title of the passage?
A. Are You Really Lack of Time?          
B. How Can You Work Efficiently?
C. What Makes Your Energy Limited?      
D. When Should You Do Exercise?
阅读理解。

     Even if you are an experienced backpacker or climber, you need to know what to do if something goes
wrong. It is not that Alaska is that much more dangerous than other places. It is no more hazardous than
elsewhere, as long as the proper precautions (预防措施) are taken. So, being prepared is important to a safe
trip.
      First of all, make sure you pack everything you will need for your trip. Even if you are traveling by car,
pack clothers and gear (用具) for backpacking. Because of the extreme weather, cars break down frequently.
Pack a coat, gloves, a hat, snow-pants, sleeping bags, candles, a flashlight, and high-energy food.
     If you are traveling by car, also pack extra belts, a spade, and a chain (铁链). If you are camping or
hiking, make sure you know how to avoid bears. If you are lost in the forest, there is no doubt that you will
encounter (遇到) them.
     However, there is no need to be nervous. Just take these precautions: make noise as you walk, bears will
avoid you; cook your food away from where you sleep, and store your food away from where you sleep, so
the bears are not attracted. Both of these should keep the bears away. However, if you do encounter a bear,
there are two different schools of thought. One is to make noise and scare the bear away. The other is to
stand still and speak softly to get the bear to leave. If you are dealing with a brown bear, you can climb a tree,
since they cannot follow. But black bears can climb. If for some reason the bear attacks, play dead. Try to
protect your head and neck, and hopefully the bear will leave its “dead” prey (捕获物).

4. The passage is mainly about ______.
A. the tips on a safe trip in Alaska
B. the very dangerous bears in Alaska
C. how to prevent your cars from being attacked by a bear
D. how to protect yourself when in trouble
阅读理解。
     Even a small reduction in salt in the diet can be a big help to the heart. A new study used a computer
model to predict how just three grams less a day would affect heart disease in the United States.
     The result:10% fewer heart attacks.8% fewer storkes.4% fewer deaths.11% fewer new cases of
heart disease. And 240 billion dollars in health care savings.
     Researchers found it could prevent 100,000 heart attacks and 92,000 deaths every year.
     The study is in the New England Journal of Medicine. Kirsten Bibbins-Domingo at the University of
California San Francisco was the lead author. She says people would not even notice a difference in
taste with three grams, or one-half teaspoon, less salt per day. The team also included researchers at
Stanford and Columbia University.
     Each gram of salt contains four hundred milligrams of sodium(钠),which is how foods may list their
salt content.
     The government says the average American man eats ten grams of salt a day. The American Heart
Association advises no more than three grams for healthy people. It says salt in the American diet has
increased fifty percent since the nineteen seventies, while blood pressures have also risen. Less salt can
mean a lower blood pressure.
     New York City Mayor Michael Bloomberg is leading an effort called the National Salt Reduction
Initiative. The idea is to put pressure on food companies and restaurants. Critics call it government
interference.
Mayor Bloomberg has already succeeded in other areas, like requiring fast food places in the city to list
calorie information. Now a study by the Seattle Children's Research Institute shows that the calorie
information on the menu can influence what parents order for their children.
1. According to the passage, what disease is not related to salt in diet?
A. cancer
B. stroke
C. blood pressure
D. heart attack
2.We can tell from the passage that now        heart attacks occur in the US every year.
A. 240,000
B. 900,000
C. 100,000
D. 92,000
3. It can be inferred from the passage that           .
A. all the heart diseases result from eating too much salt
B. the American Heart Association suggests less than 3 grams of salt a day for everyone
C. Americans ate no more than 5 grams of salt per day in the 1970s
D. the less salt one eats, the healthier he will be
4. The National Salt Reduction Initiative aims to           .
A. attract the public attention to the problem
B. require fast food places to list salt information
C. inform people of the harm that salt does to health
D. put pressure on food companies and restaurants
5. The last paragraph mainly tells us            .
A. Bloomberg has made some other efforts to improve people's health
B. Bloomberg is very successful in his career
C. parents must pay great attention to calorie information
D. a new study is being done about calorie information