Supply and demand is perhaps one of the most basic concepts of economics and it is the backbone of a market economy. Demand refers to how much of a product or service is desired by buyers. The quantity demanded is the amount of a product people are willing to buy at a certain price; the relationship between price and quantity demanded is known as the demand relationship. Supply represents how much the market can offer. The quantity supplied refers to the amount of a certain goods producers are willing to supply when receiving a certain price. The relationship between price and how much of a goods or service is supplied to the market is known as the supply relationship. Price, therefore, is a reflection of supply and demand.

   The law of demand states that, if all other factors remain equal, the higher the price of a product, the fewer people will demand that product. The amount of goods that buyers purchase at a higher price is less as the price of a product goes up, so does the opportunity cost of buying that product.

   Like the law of demand, the law of supply shows the quantities that will be sold at a certain price. But unlike the law of demand, the supply relationship shows an upward slope. This means that the higher the price, the higher the quantity supplied. Producers supply more at a higher price because selling a higher quantity at a higher price increases the whole income.

   Now that we know the laws of supply and demand, let’s turn to an example to show how supply and demand affect price.

   Imagine that a CD of your favorite band is sold for $20. Because the record company’s previous analysis showed that consumers will not demand CDs at a price higher than $20, only ten CDs were sold because the opportunity cost is too high for suppliers to produce more. If, however, the ten CDs are demanded by 20 people, the price will then rise. As a result, the rise in price should cause more CDs to be supplied as the supply relationship shows that the higher the price, the higher the quantity supplied. If, however, there are 30 CDs produced and demand is still at 20, the price will not be pushed up because the supply is more than the demand.

 

72. We know from the passage that changes in the prices of product cause changes in ______.

   A. income and expense          B. invention and production

   C. market and society            D. supply and demand

73. Look at the following tablet first, if it is up to you to make a decision to sell a widget(裝飾品), you should sell it for ______.

Price of Widgets

Number of Widgets People Want to Buy

$1.00

100

$2.00

90

$3.00

70

$4.00

40

   A. $1                         B. $2                      C. $3                      D. $4

74. The last paragraph is mainly about the importance of ______.

A. a reasonable price                                        B. finding enough producing material

C. finding out what consumers think about         D. making out the demand at market

75. The text is written mainly _____.

A. to persuade people to buy more products

B. to let people know more about a CD

C. to explain the relationships between demand, supply and price

D. to tell people how to buy things reasonably

 

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科目：高中英語 來源： 題型：閱讀理解

The U.S. Department of Labor statistics(統(tǒng)計) show that there is an oversupply of college trained workers and that this oversupply is increasing. Already there have been more than enough teachers, engineers, physicists, aerospace experts, and other specialists. Yet colleges and graduate schools continue every year to turn out highly trained people to compete for jobs that aren’t there. The result is that graduates cannot enter the professions for which they were trained and must take temporary jobs which do not require a college degree.

On the other hand, there is a great need for skilled workers of all sorts: carpenters, electricians, mechanics, plumbers, TV repairmen. These people have more work than they can deal with, and their annual incomes are often higher than those of college graduates. The old gap that white —collar workers make a better living than blue collar workers no longer holds true. The law of supply and demand now favors the skilled workmen.

The reason for this situation is the traditional myth that college degree is a passport to a prosperous future. A large part of American society matches success in life equally with a college degree. Parents begin indoctrinating(灌輸) their children with this myth before they are out of grade school. High school teachers play their part by acting as if high school education were a preparation for college rather than for life. Under this pressure the kids fall in line. Whether they want to go to college or not doesn’t matter. Everybody should go to college, so of course they must go. And every year college enrollments(入學(xué)) go up and up, and more and more graduates are overeducated for the kinds of jobs available to them.

One result of this emphasis on a college education is that many people go to college who do not belong there. Of the sixty percent of high school graduates who enter college, half of them do not graduate with their class. Many of them drop out within the first year. Some struggle on for two or three years and then give up.

It’s implied but not stated in the passage that _______.

    A. many other countries are facing the same problem

    B. white-collar workers in the US used to make more money than blue-collar workers

    C. fewer students will prefer to go to college in the future

    D. the law of supply and demand has a strong effect on American higher education

Which of the following is NOT a reason why college enrollments go up every year？   

A. Many people believe that the only way to success is a college education.

    B. Many parents want their children to go to college.

    C. High school teachers urge their students to go to college.

    D. Every young man and woman wants to go to college.

By saying that “many people go to college who do not belong there”, the author means that _______.

    A. many people who are not fit for college education go to college

    B. many people who do not have enough money go to college

    C. many people who go to college drop out within the first year

    D. many people who go to college have their hopes destroyed

We can infer from the passage that the author believes that _______.

    A. every young man and woman should go to college

    B. college education is a bad thing

    C. people with a college education should receive higher pay

    D. fewer people should go to college while more should be trained for skilled jobs

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科目：高中英語 來源：2015屆四川省高二上學(xué)期期中考試英語試卷（解析版） 題型：閱讀理解

Climate change，pollution，overuse of water and development are killing some of the world’s most famous rivers including China’s Yangtze．India’s Ganges and Africa’s Nile．WWF said on Tuesday．At the global launch of its report “World’s Top 10 Rivers at Risk”，the group said many rivers could dry out, affecting hundreds of millions of people and killing unique aquatic（水生的）life．

    “If these rivers die，millions will lose their livelihoods，biodiversity（生物多樣性）will be destroyed on a massive scale，there will be less fresh water and agriculture，resulting in less food security，”said．Rayi Singh，secretary—general of WWF—India．The report launched ahead of “World Water Day” today，also cited the Rio Grande in the United States，the Mekong and Indus in Asia，Europe’s Danube, La Plata in South America and Australia’s Murray—Darling as in need of greater protection．

    Rivers are the world’s main source of fresh water and WWF says about half of the available supply is already being used up．Dams have destroyed habitats and cut rivers off from their flood plains．while climate change could affect the seasonal water flows that feed them，the report said．Fish populations，the top source of protein and overall life support for hundreds of thousands of communities worldwide，are also being threatened, it found．．The Yangtze basin is one of the most polluted rivers in the world because of decades of heavy industrialization，damming and huge influxes（流入）of sediment（積淀）from land conversion．

  Climate change，including higher temperatures，also means serious consequences for fishery productivity，water supply and political security in Africa’s arid Nile basin．Tributaries（支流）flowing into the Ganges are drying up because of irrigation，WWF said．

1.hat is the text mainly about?

A．Saving fresh water in our life．   B．How to protect our rivers．

C．An important discovery．   D．World’s top 10 rivers are at risk．

2.We can infer from the text that _____．

A．rivers’ dying out could affect food security

B．there are four Asian rivers mentioned in the passage

C．the Yangtze is polluted thanks to the lack of enough tributaries

D．higher temperatures couldn’t affect fishery productivity

3.The top 10 rivers are fast dying as a result of the following EXCEPT _____．

A．climate change B．wasting water       C．pollution            D．dams

4.WWF is probably a name of _____．

A．a(chǎn)n organization        B．a(chǎn) newspaper      C．a(chǎn) magazine         D．a(chǎn) report

 

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科目：高中英語 來源：2013屆度遼寧省沈陽四校協(xié)作體高二上學(xué)期期中考試英語試題 題型：閱讀理解

Malaria, the world’s most widespread parasitic (寄生蟲引起的)disease, kills as many as three million people every year—almost all of whom are under five, very poor, and African. In most years, more than five hundred million cases of illness result from the disease, although exact numbers are difficult to assess because many people don't (or can’t) seek care. It is not unusual for a family earning less than two hundred dollars a year to spend a quarter of its income on malaria treatment, and what they often get no longer works. In countries like Tanzania, Mozambique, and the Gambia, no family, village, hospital, or workplace can remain unaffected for long.        

Malaria starts suddenly, with violent chills, which are soon followed by an intense fever and, often, headaches. As the parasites multiply, they take over the entire body. Malaria parasites live by eating the red blood cells they infect. They can also attach themselves to blood vessels in the brain. If it doesn’t kill you, malaria can happen again and again for years. The disease is passed on to humans by female mosquitoes infected with one of four species of a parasite. Together, the mosquito and the parasite are the most deadly couple in the history of the earth and one of the most successful. Malaria has five thousand genes, and its ability to change rapidly to defend itself and resist new drugs has made it nearly impossible to control. Studies show that mosquitoes are passing on the virus more frequently, and there are more outbreaks in cities with large populations. Some of the disease's spread is due to global warming.

For decades, the first-choice treatment for malaria parasites in Africa has been chloroquine, a chemical which is very cheap and easy to make. Unfortunately, in most parts of the world, malaria parasites have become resistant to it. Successful alternatives that help prevent resistance are already available, but they have been in short supply and are very expensive. If these drugs should fail, nobody knows what would come next.  

1.According to paragraph 1, many people don’t seek care because ________.

A. they are too poor                     

B. it is unusual to seek care

C. they can remain unaffected for long

D. there are too many people suffering from the disease

2.People suffering from malaria ________.

A. have to kill female mosquitoes         B. have ability to defend parasites

C. have their red blood cells infected    D. have sudden fever, followed by chills

3.Which of the following may be the reason for the wide spread of the disease?

A. Its resistance to global warming.     

B. Its ability to pass on the virus frequently.

C. Its outbreaks in cities with large populations.

D. Its ability to defend itself and resist new drugs.

4. It can be inferred from the passage that ________.

A. no drugs have been found to treat the disease

B. the alternative treatment is not easily available to most people

C. malaria has developed its ability to resist parasites

D. nobody knows what will be the drug to treat the disease

 

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科目：高中英語 來源：2010年普通高等學(xué)校招生全國統(tǒng)一考試（安徽卷）英語 題型：閱讀理解

The need to feed a growing population is putting much pressure on the world’s supply of water. With 97% of the world’s water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage（短缺）seems strange to someone fortunate enough to live in a high rainfull country, many of the world’s agricultural industries experience constant water shortages.

Although dams can be built to store water for agricultural use in dry areas and dry seaons, the costs of water redistribution(重新分配)are very high. Notonly is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys(山谷)are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water many flow easily through pipes to fields,but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements.

This is particularly troubling ro countries with agricultural industries in areas dependent on irrigation（灌溉）. In Texas, farmers’ overuse of irrigation water be resulted in a 25% redcution of the water stores. In the Central Valley area of south eastern USA, a huge water engineering project provided water for farming in dry vallege, but much of the water use has been poorly managed.

Saudi Arabia’s attempts to grow wheat in desert areas have been the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.

1. From the first two paragraphs we learnt that _______.

A.much of the world’s water is available for use

B.people in high rainfll countries feel lucky

C.the costs of water redistribution should be considered

D.water can be easily carried through pipes across the world

2.Which of the following is true?

A.The water  in Texas have been reduced by 75%.

B.Most industries in the world suffer from water shortagers.

C.The underground water in Saudi Arabia might run out in 50 years.

D.Good management of water use resulted from the project in the Central Valley.

3.What is most likely to be discussed in the paragreh that follows?

A.Steps to improving water use managet.

B.Ways tor redjuce the costs of builing dams.

C.Measured to dmal with worldwide water shortages.

D.Appmihes to handling the pressure on water supply.

4.The text is mainly about____________.

A.water supply and increasing population

B.water use management and agriculture

C.water redistribution and wildlife protection

D.water shornages and environmental protection.

 

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科目：高中英語 來源： 題型：閱讀理解

In cities with rent control, the city government sets the maximum rent that a landlord (房東) can charge for an apartment. Supporters of rent control argue that it protects people who are living in apartment. Their rent cannot increase; therefore, they are not in danger of losing their homes. However, the critics say that after a long time, rent control may have negative effects. Landlords know that they cannot increase their profits. Therefore, they invest in other businesses where they can increase their profits. They do not invest in new buildings which would also be rent-controlled. As a result, new apartments are not built. Many people who need apartments cannot find any. According to the critics, the end result of rent control is a shortage of apartments in the city.
Some experts argue that the minimum wage law can cause problems in the same way. The federal government sets the minimum that an employer must pay workers. The minimum helps people who generally look for unskilled, low-paying jobs. However, if the minimum is high, employers may hire fewer workers. They will replace workers with machinery. Therefore, other things being equal, the number of workers that employers want decreases. Thus, critics hold the opinion that an increase in the minimum wage may cause unemployment. Some poor people may find themselves without jobs instead of with jobs at the minimum wage.
Supporters of the minimum wage say that it helps people keep their dignity. Because of the law, workers cannot sell their services for less than the minimum. Furthermore, employers cannot force workers to accept jobs at unfair wages.
Economic theory predicts the results of economic decision, such as decisions about farm production, rent control, and the minimum wage. The predictions may be corrected only if “other things are equal”. Economists do not agree on some of the predictions. They also do not agree on the value of different decisions. Some economists support a particular decision while others criticize it. Economists do agree, however, that there are no simple answers to economic questions.

  1. 1.

    There is the possibility that setting maximum rent may________.

    1. A.
      cause a shortage of apartments
    2. B.
      worry those who rent apartments as homes.
    3. C.
      increase the profits of landlords.
    4. D.
      encourage landlords to invest in building apartments.
  2. 2.

    We can safely say that rent control_________.

    1. A.
      will always benefit those who rent apartments.
    2. B.
      is unnecessary.
    3. C.
      will probably bring inactive effects in the long run.
    4. D.
      is necessary under all conditions
  3. 3.

    There will be the problem of unemployment if ________________.

    1. A.
      the minimum wage is set too high..
    2. B.
      the minimum wage is set too early.
    3. C.
      the workers are unskilled.
    4. D.
      the maximum wage is set for poor workers.
  4. 4.

    The passage tells us about _______________.

    1. A.
      the relationship between supply and demand.
    2. B.
      the possible results of government controls.
    3. C.
      the necessity of government control.
    4. D.
      the urgency of getting rid of government control.
  5. 5.

    Which of the following statements is NOT true?

    1. A.
      The results of economic decisions cannot always be predicted.
    2. B.
      Minimum wage cannot always protect employees.
    3. C.
      Economic theory can help predict the results of economic decision if other factors are not changing.
    4. D.
      Economists usually have the same prediction about an economic decision.

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