单选题The water of the Great Salt Lake is _____ seawater.A saltier than that ofB as salty as that ofC saltier thanD so salty as

题目
单选题
The water of the Great Salt Lake is _____ seawater.
A

saltier than that of

B

as salty as that of

C

saltier than

D

so salty as


相似考题

3.请阅读短文,完成此题。 When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained. The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation. Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas. A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water. In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.Which of the following statements is TRUE according to the passage? 查看材料 A.Oceanic salinity has great effect on sea life. B.Many factors combine to cause changes in oceanic salinity. C.The movement of the water is related to the amount of salt. D.The temperature of the water has much to do with the oceanic salinity.

更多“The water of the Great Salt Lake is _____ seawater.”相关问题
  • 第1题:

    共用题干
    Where Has the Salt Come from?

    Every now and then,we meet a fact about our earth that makes us feel strange and no
    answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
    How did it get there?
    We simply do not know how the salt got into the ocean!We do know,of course,that
    salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
    surface is constantly being dissolved(溶解)and is passing into the ocean.
    But we do not know whether this can explain the huge quantity of salt in oceans.If all
    the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
    mile thick. Such a wall would reach once around the world at the Equator(赤道)!
    The common salt that we all use is produced from seawater or the water of salt lakes,
    from salt springs(源泉)and from deposits of rock salt. The concentration(浓度)of salt in
    seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
    which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
    salt!
    On the average, a gallon(加仑)of seawater contains about a quarter of a pound of
    salt.The beds of rock salt that are found in various parts of the world were all originally
    formed by the evaporation(蒸发)of seawater millions of years ago. It is believed that the
    thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
    been evaporated.
    Most commercial salt is obtained from rock salt.The usual method is to drill wells(井)
    down to the salt beds. Pure water is pumped down(抽进去)through a pipe. The water
    dissolves the salt and it is forced through another pipe up to the surface.


    A:Right
    B:Wrong
    C:Not mentioned

    答案:B
    解析:

  • 第2题:

    共用题干
    Where Has the Salt Come from?

    Every now and then,we meet a fact about our earth that makes us feel strange and no
    answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
    How did it get there?
    We simply do not know how the salt got into the ocean!We do know,of course,that
    salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
    surface is constantly being dissolved(溶解)and is passing into the ocean.
    But we do not know whether this can explain the huge quantity of salt in oceans.If all
    the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
    mile thick. Such a wall would reach once around the world at the Equator(赤道)!
    The common salt that we all use is produced from seawater or the water of salt lakes,
    from salt springs(源泉)and from deposits of rock salt. The concentration(浓度)of salt in
    seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
    which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
    salt!
    On the average, a gallon(加仑)of seawater contains about a quarter of a pound of
    salt.The beds of rock salt that are found in various parts of the world were all originally
    formed by the evaporation(蒸发)of seawater millions of years ago. It is believed that the
    thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
    been evaporated.
    Most commercial salt is obtained from rock salt.The usual method is to drill wells(井)
    down to the salt beds. Pure water is pumped down(抽进去)through a pipe. The water
    dissolves the salt and it is forced through another pipe up to the surface.

    The author is sure that the dissolved salt from the earth's surface is the only source of the huge quantity of salt found in oceans.
    A:Right
    B:Wrong
    C:Not mentioned

    答案:B
    解析:

  • 第3题:

    The largest lake in Britain is( ).

    A.the Lake Neagh
    B.Windermere Water
    C.Coniston Water
    D.the Lake District

    答案:A
    解析:
    英国地理。题目问英国最大的湖泊是什么湖,答案是Lake Neagh(内伊湖)。英格兰西北部的湖区(the Lake District)是英国著名的旅游景点,也是著名的湖畔诗人华兹华斯(William Wordsworth)的家乡。

  • 第4题:

    单选题
    Since 1960, the fast-growing town of Hotstone, Arizona, has drawn water from the Gray River, which feeds Lake Mudfish. If the town’s water use continues to grow at its present rate, in about 20 years the water level of Lake Mudfish will inevitably decrease to the point that it can no longer support its biologically fragile population of fish.  The prediction above is based on which of the following assumptions?
    A

    As the town’s water requirements grow, it will not be able to meet those requirements by drawing on water sources other than the Gray River.

    B

    Since 1960, the lake’s population of fish has become more biologically fragile.

    C

    The amount of water that the lake loses to evaporation each year will increase over the next two decades.

    D

    There are multiple sources of water besides the Gray River that feed into Lake Mudfish.

    E

    The town of Hotstone will be able to reverse its trend of increasing water use if it implements an aggressive water conservation program.


    正确答案: B
    解析:
    由文段的内容可知,Mudfish湖之所以会干涸是因为Gray River的水都被用来提供给周边的Hotstone和Arizona,所以可知本题应选A项。

  • 第5题:

    单选题
    请阅读 Passage 1,完成第 21~25小题。Passage 1These days,many large city buildings are equipped with their own air-conditioning systems.These systems help keep the buildings cool,but they can also damage the environment.Since they use a lot of electricity,for instance,they contribute indirectly to global warming.In addition,the water that flows through the systems is often cooled using chemicals called chlorofluorocarbons,or CFCs,that are believed to damage the Earth's ozone layer.Recently,though,a system has been built in the city of Toronto,Canada,that cools buildings with little damage to the environment. In the traditional air-conditioning systems found in most large buildings,water is pumped through the building in a continuous cycle.The water is first cooled to a temperature of 4℃ in machines called chillers.It is then sent to individual units that cool the air in each room.As the water flows through the building,it gradually becomes warmer.Finally,it reaches the roof ,where it is left to cool down naturally in a water tower.After that it is returned to the chillers,where the cycle begins again.Toronto lies on the shore of Lake Ontario,one of North America's Great Lakes,and the new system makes use of cold water taken from about 80 meters below the surface of the lake.At this depth,the water in the lake remains at 4℃ all year round.This is exactly the temperature to which the water in air-conditioning systems is cooled.However,the water from the lake is not pumped directly into the air-conditioning systems.Instead,it is used to cool the water that is already inside the air-conditioning systems.After that,the lake water is added to the city's ordinary water supply.Enwave,the company that developed this deep-lake cooling system,says that it uses 75 percent less energy than traditional air conditioning.And since no CFCs are used,no damage can be caused to the ozone layer.Not every city is located next to a large lake,but experts believe that systems like the one being used in Toronto could be built elsewhere by using other natural sources of cold water.What is the function of the chillers in a traditional air-conditioning system?
    A

    They pump the air continuously to the units in each room.

    B

    They lower the temperature of the water in the system.

    C

    They help the water cool down naturally on the roof .

    D

    They gradually clean the water as it flows through the building.


    正确答案: A
    解析:

  • 第6题:

    单选题
    If you swim in a river or lake, be sure to investigate________is below the water surface. Often there are rocks or branches hidden in the water.
    A

    what

    B

    who

    C

    that

    D

    whoever


    正确答案: C
    解析:

  • 第7题:

    单选题
    A salinity indicator is used to determine the ().
    A

    cause of salt contamination

    B

    location of salt water contamination

    C

    chemical makeup of feed-water

    D

    level of alkalinity in condensate


    正确答案: D
    解析: 暂无解析

  • 第8题:

    单选题
    Passage2         Questions 6 to 10 are based on the following passage.         Salt is as necessary to life as water. In many areas of Africa people once drank the urine(尿)of animals because they had no other source of salt. Without salt, human beings die.          The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys(肾) and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst.      In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.7 In order to adjust to the loss of salt, the body______.
    A

    loses some blood

    B

    speeds up its secretion of water

    C

    speeds up its secretion of salt

    D

    is drying up slowly


    正确答案: A
    解析:

  • 第9题:

    单选题
    In motorships,there are two main circuits, ().
    A

    one salt water, one fresh water

    B

    one salt water, one fuel

    C

    one fresh water, one fuel

    D

    one steam, one fuel


    正确答案: C
    解析: 暂无解析

  • 第10题:

    单选题
    ()provides strength and strong space for fule,lubricating oil,fresh water,salt(ballast)water and potable water.
    A

    The double bottom

    B

    The cofferdam

    C

    The navigating bridge

    D

    The superstructure


    正确答案: A
    解析: 暂无解析

  • 第11题:

    单选题
    请阅读 Passage 1,完成第 21~25小题。Passage 1These days,many large city buildings are equipped with their own air-conditioning systems.These systems help keep the buildings cool,but they can also damage the environment.Since they use a lot of electricity,for instance,they contribute indirectly to global warming.In addition,the water that flows through the systems is often cooled using chemicals called chlorofluorocarbons,or CFCs,that are believed to damage the Earth's ozone layer.Recently,though,a system has been built in the city of Toronto,Canada,that cools buildings with little damage to the environment. In the traditional air-conditioning systems found in most large buildings,water is pumped through the building in a continuous cycle.The water is first cooled to a temperature of 4℃ in machines called chillers.It is then sent to individual units that cool the air in each room.As the water flows through the building,it gradually becomes warmer.Finally,it reaches the roof ,where it is left to cool down naturally in a water tower.After that it is returned to the chillers,where the cycle begins again.Toronto lies on the shore of Lake Ontario,one of North America's Great Lakes,and the new system makes use of cold water taken from about 80 meters below the surface of the lake.At this depth,the water in the lake remains at 4℃ all year round.This is exactly the temperature to which the water in air-conditioning systems is cooled.However,the water from the lake is not pumped directly into the air-conditioning systems.Instead,it is used to cool the water that is already inside the air-conditioning systems.After that,the lake water is added to the city's ordinary water supply.Enwave,the company that developed this deep-lake cooling system,says that it uses 75 percent less energy than traditional air conditioning.And since no CFCs are used,no damage can be caused to the ozone layer.Not every city is located next to a large lake,but experts believe that systems like the one being used in Toronto could be built elsewhere by using other natural sources of cold water.Which of the following is true?
    A

    Enwave's system is said to work only in cities located near the Great Lakes.

    B

    The water deep in Lake Ontario always remains at the same temperature.

    C

    Experts warn that the use of CFCs in Enwave' s system will add to global warming.

    D

    Toronto is now searching for new natural sources of water to use in its water supply.


    正确答案: C
    解析:

  • 第12题:

    单选题
    请阅读 Passage 1,完成第 21~25小题。Passage 1These days,many large city buildings are equipped with their own air-conditioning systems.These systems help keep the buildings cool,but they can also damage the environment.Since they use a lot of electricity,for instance,they contribute indirectly to global warming.In addition,the water that flows through the systems is often cooled using chemicals called chlorofluorocarbons,or CFCs,that are believed to damage the Earth's ozone layer.Recently,though,a system has been built in the city of Toronto,Canada,that cools buildings with little damage to the environment. In the traditional air-conditioning systems found in most large buildings,water is pumped through the building in a continuous cycle.The water is first cooled to a temperature of 4℃ in machines called chillers.It is then sent to individual units that cool the air in each room.As the water flows through the building,it gradually becomes warmer.Finally,it reaches the roof ,where it is left to cool down naturally in a water tower.After that it is returned to the chillers,where the cycle begins again.Toronto lies on the shore of Lake Ontario,one of North America's Great Lakes,and the new system makes use of cold water taken from about 80 meters below the surface of the lake.At this depth,the water in the lake remains at 4℃ all year round.This is exactly the temperature to which the water in air-conditioning systems is cooled.However,the water from the lake is not pumped directly into the air-conditioning systems.Instead,it is used to cool the water that is already inside the air-conditioning systems.After that,the lake water is added to the city's ordinary water supply.Enwave,the company that developed this deep-lake cooling system,says that it uses 75 percent less energy than traditional air conditioning.And since no CFCs are used,no damage can be caused to the ozone layer.Not every city is located next to a large lake,but experts believe that systems like the one being used in Toronto could be built elsewhere by using other natural sources of cold water.What is one advantage of Enwave 's new system?
    A

    It keeps buildings much cooler than other methods.

    B

    It can be used by large cities anywhere in the world.

    C

    It is much more energy-efficient than traditional systems.

    D

    It keeps water from being used for more than one purpose.


    正确答案: B
    解析:

  • 第13题:

    共用题干
    Where Has the Salt Come from?

    Every now and then,we meet a fact about our earth that makes us feel strange and no
    answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
    How did it get there?
    We simply do not know how the salt got into the ocean!We do know,of course,that
    salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
    surface is constantly being dissolved(溶解)and is passing into the ocean.
    But we do not know whether this can explain the huge quantity of salt in oceans.If all
    the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
    mile thick. Such a wall would reach once around the world at the Equator(赤道)!
    The common salt that we all use is produced from seawater or the water of salt lakes,
    from salt springs(源泉)and from deposits of rock salt. The concentration(浓度)of salt in
    seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
    which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
    salt!
    On the average, a gallon(加仑)of seawater contains about a quarter of a pound of
    salt.The beds of rock salt that are found in various parts of the world were all originally
    formed by the evaporation(蒸发)of seawater millions of years ago. It is believed that the
    thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
    been evaporated.
    Most commercial salt is obtained from rock salt.The usual method is to drill wells(井)
    down to the salt beds. Pure water is pumped down(抽进去)through a pipe. The water
    dissolves the salt and it is forced through another pipe up to the surface.

    Beds of rock salt are found in every part of the world.
    A:Right
    B:Wrong
    C:Not mentioned

    答案:A
    解析:

  • 第14题:

    共用题干
    Where Has the Salt Come from?

    Every now and then,we meet a fact about our earth that makes us feel strange and no
    answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
    How did it get there?
    We simply do not know how the salt got into the ocean!We do know,of course,that
    salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
    surface is constantly being dissolved(溶解)and is passing into the ocean.
    But we do not know whether this can explain the huge quantity of salt in oceans.If all
    the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
    mile thick. Such a wall would reach once around the world at the Equator(赤道)!
    The common salt that we all use is produced from seawater or the water of salt lakes,
    from salt springs(源泉)and from deposits of rock salt. The concentration(浓度)of salt in
    seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
    which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
    salt!
    On the average, a gallon(加仑)of seawater contains about a quarter of a pound of
    salt.The beds of rock salt that are found in various parts of the world were all originally
    formed by the evaporation(蒸发)of seawater millions of years ago. It is believed that the
    thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
    been evaporated.
    Most commercial salt is obtained from rock salt.The usual method is to drill wells(井)
    down to the salt beds. Pure water is pumped down(抽进去)through a pipe. The water
    dissolves the salt and it is forced through another pipe up to the surface.

    If all the oceans were dried up,the salt thus obtained would be extremely great in size.
    A:Right
    B:Wrong
    C:Not mentioned

    答案:A
    解析:

  • 第15题:

    The Great Salt Lake lies in northern ()

    • A、Idaho
    • B、Arizona
    • C、Nevada
    • D、Utah

    正确答案:D

  • 第16题:

    单选题
    Passage2         Questions 6 to 10 are based on the following passage.         Salt is as necessary to life as water. In many areas of Africa people once drank the urine(尿)of animals because they had no other source of salt. Without salt, human beings die.          The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys(肾) and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst.      In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.6 Some African people once drank animal urine______.
    A

    when they were going to die

    B

    because they were thirsty

    C

    because there was little salt

    D

    because they were short of water


    正确答案: B
    解析:

  • 第17题:

    单选题
    Passage2         Questions 6 to 10 are based on the following passage.         Salt is as necessary to life as water. In many areas of Africa people once drank the urine(尿)of animals because they had no other source of salt. Without salt, human beings die.          The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys(肾) and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst.      In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.10 What is the main idea of the passage?
    A

    Salt is very important.

    B

    If their blood salt level is not constant, human beings may die.

    C

    The amount of salt in the body is secreted.

    D

    People can die of thirst.


    正确答案: A
    解析:

  • 第18题:

    单选题
    What does salt water draft mean?().
    A

    It means summer draft

    B

    It means maximum draft

    C

    It means fresh water draft

    D

    It means seawater draft


    正确答案: D
    解析: 暂无解析

  • 第19题:

    单选题
    () is used for cylinder and cylinder head, the salt water is used for cooling the lubricating oil, the fresh water in the coolers and the charging air in the air cooler.
    A

    The fuel oil

    B

    The lube oil

    C

    The sea water

    D

    The fresh water


    正确答案: C
    解析: 暂无解析

  • 第20题:

    单选题
    请阅读 Passage 1,完成第 21~25小题。Passage 1These days,many large city buildings are equipped with their own air-conditioning systems.These systems help keep the buildings cool,but they can also damage the environment.Since they use a lot of electricity,for instance,they contribute indirectly to global warming.In addition,the water that flows through the systems is often cooled using chemicals called chlorofluorocarbons,or CFCs,that are believed to damage the Earth's ozone layer.Recently,though,a system has been built in the city of Toronto,Canada,that cools buildings with little damage to the environment. In the traditional air-conditioning systems found in most large buildings,water is pumped through the building in a continuous cycle.The water is first cooled to a temperature of 4℃ in machines called chillers.It is then sent to individual units that cool the air in each room.As the water flows through the building,it gradually becomes warmer.Finally,it reaches the roof ,where it is left to cool down naturally in a water tower.After that it is returned to the chillers,where the cycle begins again.Toronto lies on the shore of Lake Ontario,one of North America's Great Lakes,and the new system makes use of cold water taken from about 80 meters below the surface of the lake.At this depth,the water in the lake remains at 4℃ all year round.This is exactly the temperature to which the water in air-conditioning systems is cooled.However,the water from the lake is not pumped directly into the air-conditioning systems.Instead,it is used to cool the water that is already inside the air-conditioning systems.After that,the lake water is added to the city's ordinary water supply.Enwave,the company that developed this deep-lake cooling system,says that it uses 75 percent less energy than traditional air conditioning.And since no CFCs are used,no damage can be caused to the ozone layer.Not every city is located next to a large lake,but experts believe that systems like the one being used in Toronto could be built elsewhere by using other natural sources of cold water.What happens in the end to the water from Lake Ontario?
    A

    It is used by the residents of Toronto.

    B

    It is returned to a place deep in the lake.

    C

    It is cooled down before being used again.

    D

    It is added to the water inside air-conditioning systems.


    正确答案: B
    解析:

  • 第21题:

    单选题
    How did the immigrants in Salt Lake City feel about “Operation Safe Travel”?
    A

    Guilty.

    B

    Offended.

    C

    Disappointed.

    D

    Discouraged.


    正确答案: C
    解析:
    细节题。B项同义替换了第三段。“offended”替换“angered”,“Operation Safe Travel”替换“were angered at the arrest”。guilty感到内疚的,感到惭愧的;disappointed失望的;discouraged气馁的。

  • 第22题:

    单选题
    Passage2         Questions 6 to 10 are based on the following passage.         Salt is as necessary to life as water. In many areas of Africa people once drank the urine(尿)of animals because they had no other source of salt. Without salt, human beings die.          The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys(肾) and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst.      In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.8 Which of the following statements is NOT the result of a lack of salt in the body?
    A

    The body secretes more water.

    B

    The body dries up.

    C

    The person dies of thirst.

    D

    The person gets fatter.


    正确答案: B
    解析:

  • 第23题:

    单选题
    请阅读 Passage 1,完成第 21~25小题。Passage 1These days,many large city buildings are equipped with their own air-conditioning systems.These systems help keep the buildings cool,but they can also damage the environment.Since they use a lot of electricity,for instance,they contribute indirectly to global warming.In addition,the water that flows through the systems is often cooled using chemicals called chlorofluorocarbons,or CFCs,that are believed to damage the Earth's ozone layer.Recently,though,a system has been built in the city of Toronto,Canada,that cools buildings with little damage to the environment. In the traditional air-conditioning systems found in most large buildings,water is pumped through the building in a continuous cycle.The water is first cooled to a temperature of 4℃ in machines called chillers.It is then sent to individual units that cool the air in each room.As the water flows through the building,it gradually becomes warmer.Finally,it reaches the roof ,where it is left to cool down naturally in a water tower.After that it is returned to the chillers,where the cycle begins again.Toronto lies on the shore of Lake Ontario,one of North America's Great Lakes,and the new system makes use of cold water taken from about 80 meters below the surface of the lake.At this depth,the water in the lake remains at 4℃ all year round.This is exactly the temperature to which the water in air-conditioning systems is cooled.However,the water from the lake is not pumped directly into the air-conditioning systems.Instead,it is used to cool the water that is already inside the air-conditioning systems.After that,the lake water is added to the city's ordinary water supply.Enwave,the company that developed this deep-lake cooling system,says that it uses 75 percent less energy than traditional air conditioning.And since no CFCs are used,no damage can be caused to the ozone layer.Not every city is located next to a large lake,but experts believe that systems like the one being used in Toronto could be built elsewhere by using other natural sources of cold water.What is one problem with traditional air-conditioning systems?
    A

    The chemicals they use sometimes pollute the water supply.

    B

    They often damage the buildings that they are trying to cool.

    C

    There are not enough CFCs in the world to cool all the buildings.

    D

    The method they use to cool water is thought to harm the ozone layer.


    正确答案: A
    解析: