多选题Consider each of the choices separately and select all that apply.　 Which of these can be inferred from the fact that the French built orangeries for certain tropical plants?AGreenhouses may be used to keep plants at a moderate temperatureBThe climate of France is unsuited to growing tropical plants outdoors.CLouis ⅩⅣ was a frequent and enthusiastic traveler to Africa and Asia

考题 CPlants can’t communicate by moving or making sounds, as most animals do. Instead, plants produce volatile compounds, chemicals that easily change from a liquid to a gas. A flower’s sweet smell, for example, comes from volatile compounds that the plant produces to attract insects such as bugs and bees.Plants can also detect volatile compounds produced by other plants. A tree under attack by hungry insects, for instance, may give off volatile compounds that let other trees know about the attack, In response, the other trees may send off chemicals to keep the bugs away- or even chemicals that attract the bugs’ natural enemies.Now scientists have created a quick way to understand what plants are saying: a chemical sensor(传感器) called an electronic nose. The “e-nose” can tell compounds that crop plants make when they’re attacked. Scientists say the e-nose could help quickly detest whether plants are being eaten by insects. But today the only way to detect such insects is to visually inspect individual plants. This is a challenging task for managers of greenhouses, enclosed gardens that can house thousands of plants.The research team worked with an e-nose that recognizes volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds. Based on these interactions, the e-nose gives off electronic signals that the scientists analyze using computer software.To test the nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all common greenhouse crops. Then the scientists collected samples of air around damaged leaves from each type of crop. These plants had been damaged by insects, or by scientists who made holes in the leaves with a hole punch (打孔器).The e-nose, it turns out, could identify healthy cucumber, pepper and tomato plants based on the volatile compounds they produce. It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage – by insects or with a hole punch – had been done to the tomato leaves.With some fine tuning, a device like the e-nose could one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this could also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareve, a biochemist at Purdue University in West Lafayette, Ind. who studies smells of flowers and plants. Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future.49. We learn from the text that plants communicate with each other by______.A. making some sounds B. waving their leavesC. producing some chemicals D. sending out electronic signals

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考题 Which of the following are true statements regarding the characteristics of OSPF areas? Select all that apply.() A. All OSPF networks require the use of multiple areasB. Multiple OSPF areas must connect to area 0C. Single area OSPF networks must be configured in area 1D. Areas can be assigned any number from 0 to 63535E. Area 0 is called the backbone areaF. Each OSPF area need to be configured with a loopback interface

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考题 Which statement describes the rule of split horizon?() A. Only router can split boundaries(horizons)between concentric networks.B. All distance vector protocols require fall routes that may cause momentary loops as the topology changes.C. Networks can only remain fully converged if all information about routes is sent out all active interfaces.D. Information about a route should not be sent back in the direction from which the original update came.E. Each AS must keep routing tables converged to prevent dead routes from being advertised across the AS boundary.

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考题 AWhy do plants grow in some places and not in others? Why does some land have so much growing on it，while other land has almost no plants growing on it at all?To grow plants need several things． One is warmth． In very cold places almost nothing grows． Plants also need water． In very dry parts of the earth only a few unusual plants can grow． That's why dry deserts everywhere are almost not covered by trees or grass．Plants must also have a place in which to f，ut down their roots and grow． They find it diffi-culr to grow on hard land． The town is built on hard land． The plants here have only the soil found between the cracks of the stones Io grow in．Another thing plants must have before they can grow is food．Whar will happen if we try to make things grow on the sandy beach? A few plants，such as beach grass，will grow in sand，L ut most plants won-t． Even if the weather is warm enough．and we water the plants each day． Many of them will die because the sand on this beach has al-most no food for plants．( )21． According to the passage，plants need _________ things to grow well．A． twoB． threeC． fourD． five

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考题 29． Why are green plants and grass helpful?A． Because they can hold the water．B． Because they can stop the wind from blowing the earth away．C． Because they can keep the earth wet．D．All the above．

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考题共用题干第三篇Only special plants can survive in the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃.Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds which drive small-sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring.Grasses and flowers in desert survive from one year to the next by existing through the long, hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time that the water from the spring rains disappears—ust a few weeks after it falls一such plants no longer need any.The perennials（多年生植物）have special features which enable them to survive as plants for several years. Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in a short time.The small shoot system,on the other hand,considerably limits water loss by evaporation（蒸发）.Another feature of many desert perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation during the dry season.Then,in the next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.We can learn from the passage that the shoot system of the perennials_________.A:can help the perennials absorb less of the sun's rayB:decides the appearance of the perennials in desertC:limits the function of the perennials' branchesD:may prevent the perennials from losing much water

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考题共用题干第三篇Only special plants can survive in the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃.Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds which drive small-sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring.Grasses and flowers in desert survive from one year to the next by existing through the long, hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time that the water from the spring rains disappears—ust a few weeks after it falls一such plants no longer need any.The perennials（多年生植物）have special features which enable them to survive as plants for several years. Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in a short time.The small shoot system,on the other hand,considerably limits water loss by evaporation（蒸发）.Another feature of many desert perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation during the dry season.Then,in the next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.According to the passage,spring is the best time for plants in desert_________.A:to find a shady placeB:to get water for their growthC:to reduce water lossD:to enjoy the sunshine

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考题共用题干第三篇Only special plants can survive in the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃.Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds which drive small-sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring.Grasses and flowers in desert survive from one year to the next by existing through the long, hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time that the water from the spring rains disappears—ust a few weeks after it falls一such plants no longer need any.The perennials（多年生植物）have special features which enable them to survive as plants for several years. Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in a short time.The small shoot system,on the other hand,considerably limits water loss by evaporation（蒸发）.Another feature of many desert perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation during the dry season.Then,in the next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.Some grasses and flowers can survive in the desert because__________.A:they need little water for their survivalB:they bear long roots and the seeds are fit for dry weatherC:they stay in the form of seeds to wait for the right armiount of waterD:with long roots,they do not depend on the rain to get enough water

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考题共用题干第三篇Only special plants can survive in the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃.Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds which drive small-sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring.Grasses and flowers in desert survive from one year to the next by existing through the long, hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time that the water from the spring rains disappears—ust a few weeks after it falls一such plants no longer need any.The perennials（多年生植物）have special features which enable them to survive as plants for several years. Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in a short time.The small shoot system,on the other hand,considerably limits water loss by evaporation（蒸发）.Another feature of many desert perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation during the dry season.Then,in the next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.Ordinary plants can not survive the desert weather as a result of the following except for_________.A:the strong windsB:the strong sun's rayC:the long summer daysD:the high soil temperature

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考题共用题干 Plants in DesertOnly special plants can survive the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃．Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds that drive small,sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring.Grasses and flowers in desert survive from one year to the next by existing through the long,hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time the water from the spring rains disappears-just a few weeks after it falls-such plants no longer need any.The perennials（多年生植物）have special features that enable them to survive as plants for several years.Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in short time.The small shoot system,on the other hand,considerably limits water loss by evaporation（蒸发）.Another feature of many perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter.This reduces their water loss by evaporation during the dry season.Then,in next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.A:Right B:Wrong C:Not mentioned

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考题共用题干 Plants in DesertOnly special plants can survive the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃．Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds that drive small,sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring. Grasses and flowers in desert survive from one year to the next by existing through the long,hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time the water from the spring rains disappears-just a few weeks after it falls-such plants no longer need any.The perennials（多年生植物）have special features that enable them to survive as plants for several years.Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in short time. The small shoot system,on the other hand,considerably limits water ioss by evaporation（蒸发）.Another feature of many perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter.This reduces their water loss by evaporation during the dry season.Then,in next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.Grasses and flowers in the desert whose life cycles are short show their ability to adapt to the quick disappearance of rainwater there after it falls in spring.A:Right B:Wrong C:Not mentioned

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考题共用题干 Plants in DesertOnly special plants can survive the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃．Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds that drive small,sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring. Grasses and flowers in desert survive from one year to the next by existing through the long,hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time the water from the spring rains disappears-just a few weeks after it falls-such plants no longer need any.The perennials（多年生植物）have special features that enable them to survive as plants for several years.Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in short time. The small shoot system,on the other hand,considerably limits water ioss by evaporation（蒸发）.Another feature of many perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter.This reduces their water loss by evaporation during the dry season.Then,in next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.Ordinary plants are unable to survive in the desert mainly because of the changeable weather.A:Right B:Wrong C:Not mentioned

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考题共用题干 Plants in DesertOnly special plants can survive the terrible climate of a desert,for these are regions where the annual range of the soil temperature can be over 75℃．Furthermore,during the summer there are few clouds in the sky to protect plants from the sun's ray.Another problem is the fact that there are frequently strong winds that drive small,sharp particles of sand into the plants,tearing and damaging them.The most difficult problem for all forms of plant life,however,is the fact that the entire annual rainfall occurs during a few days or weeks in spring. Grasses and flowers in desert survive from one year to the next by existing through the long,hot,dry season in the form of seeds.These seeds remain inactive unless the right amount of rain falls.If no rain falls,or if insufficient rain falls,they wait until the next year,or even still the next.Another factor that helps these plants to survive is the fact that their life cycles are short.By the time the water from the spring rains disappears-just a few weeks after it falls-such plants no longer need any.The perennials（多年生植物）have special features that enable them to survive as plants for several years.Thus,nearly all desert perennials have extensive root systems below ground and a small shoot system above ground.The large root network enables the plant to absorb as much water as possible in short time. The small shoot system,on the other hand,considerably limits water ioss by evaporation（蒸发）.Another feature of many perennials is that after the rainy season they lose their leaves in preparation for the long,dry season,just as trees in wetter climates lose theirs in preparation for the winter.This reduces their water loss by evaporation during the dry season.Then,in next rainy season,they come fully alive once more,and grow new branches,leaves and flowers,just as the grasses and flowers in desert do.The shoot system of perennials can help the plants absorb less of the sun's ray.A:Right B:Wrong C:Not mentioned

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考题共用题干第三篇Citizen ScientistsUnderstanding how nature responds to climate change will require monitoring key life cycle events一 flowering,the appearance of leaves and the first frog calls of the spring一all around the world.But ecologists can't be everywhere so they're turning to non-scientists,sometimes called citizen scientists,for help.Climate scientists are not present everywhere.Because there are so many places in the world and not enough scientists to observe all of them,they're asking for your help in observing signs of climate change across the world.The citizen scientist movement encourages ordinary people to observe a very specificresearch interest一birds,trees,flowers budding,etc.and send their observations to a giant database to be observed by professional scientists.This helps a small number of scientists track a large amount of data that they would never be able to gather on their own.Much like citizen journalists helping large publications cover a hyper-local beat,citizen scientists are ready for the conditions where they live in.All that's needed to become one is a few minutes each day or each week to gather data and send them in.A group of scientists and educators launched an organization last year called the National Phenology Network."Phenology"is what scientists call the study of the timing of events in nature.One of the group's first efforts relies on scientists and non-scientists alike to collect data about plant flowering and leafing eveiy year.The program,called Project BudBurst,collects life cycle data on a variety of common plants from across the United States.People participating in the project一which is open to every- one一record their observations on the Project BudBurst website."People don't have to be plant experts一they just have to look around and see what's in their neighbor- hood,"says Jennifer Schwartz,an education consultant with the project."As we collect these data,we'll be able to make an estimate of how plants and communities of plants and animals will respond as the climatechanges."What is the final purpose of Project BudBurst?A:To study when plants will have their first buds.B:To find out the types of plants in the neighborhood.C:To collect life cycle data on a variety of common plants from across the United States.D:To investigate how plants and animals will respond as the climate changes.

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考题多选题The ratio of two quantities is 4 to 5. If each of the quantities is increased by 3, which of the following could be the ratio of these two new quantities? (Indicate all answer choices that apply.)A7/8B11/13C23/28

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考题多选题For Question 2, consider each of the choices separately and select all that apply.　 The passage supports which of the following statements about Rembrandt?AMost of Rembrandt’s contemporaries avoided the use of humble models for their paintingsBRembrandt achieved enhanced artistic effect through the use f a unique method.CRembrandt saw artistic value in subject matter outside the mainstream.

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考题多选题Consider each of the choices separately and select all that apply.　 According to the passage, which word or words might describe Rohmer’s style?ADynamicBDialogue-drivenCPhilosophical

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考题单选题For Question 2, consider each of the choices separately and select all that apply.　 Which of the following can be inferred from the passage regarding research into the memory-altering drug?A It is currently applicable to many types of traumatic situations.B Research is ongoing, and the treatment remains controversial.C Our sense of self as well as our personal history is essentially static.

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考题多选题Consider each of the choices separately and select all that apply.　 Which of the following inferences can be made the information given in the passage?ALeonard Fuchs probably never actually saw a fuchsia plant.BCharles Plumier was a student of Fuchs’s at Tubingen.CPlumier’s book of plants included species from the Caribbean.

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考题多选题For Question 1, consider each of the choices separately and select all that apply.　 Which of the following statements about Edison can be inferred from the passage?AEdison was one of the world’s most esteemed and influential inventors.BConcrete furniture was the only one of Edison’s inventions to ultimately fail.CThe light bulb and the phonograph were extremely successful inventions by Edison.

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考题多选题For Question 2, consider each of the choices separately and select all that apply.　 Which of the following statements about the portrait is supported by the passage?AThe portrait is the subject of ongoing controversy.BThe portrait was of a single unidentified woman.CThe portrait’s model was smiling as the picture was painted.

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考题多选题For Question 1, consider each of the choices separately and select all that apply.　 The passage suggests which of the following about gender in Western culture?AMost, if not all, members of modern Western civilization consider themselves either male or female.BContemporary Western civilization does not believe in the concept of hijra.CThe idea of male／female binary gender is not generally considered the norm of contemporary Western civilization.

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考题多选题Consider each of the choices separately and select all that apply.　 According to the author, what did Giovanni Riccioli do wrong?ANamed moon structures for bodies of waterBMistook lava flows for marine featuresCRenamed objects on Grimaldi’s lunar map

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考题多选题Consider each of the choices separately and select all that apply.　 If a father of four children carries the Huntington’s mutation, which of these is true?ATwo of the four children may inherit the mutation.BTwo of the four children may have the disease.CTwo of the four children may end up disease free.

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考题单选题Consider each of the choices separately and select all that apply.　 The author implies which of the following about Lord Curzon?A He was a descendent of Sir Edward Dalyngrigge.B His love of architecture assisted British tourism.C He lived in Bodiam Castle from 1917 until his death.

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考题单选题Consider each of the choices separately and select all that apply.　 Paragraph two of the passage suggests that La Solidaridad was a success because it ______.A had modest goals that it stuck to year after yearB reached thousands of people who longed for leadershipC touched a handful of leaders who took up its cause

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考题多选题For questions 2 and 3, consider each of the choices separately and select all that apply.　 Which fact or facts about purple loosestrife add to its power of endurance?AIt has a great ability to cross-pollinate.BIt easily adapts to environmental change.CIt has spiky stems and flowers.

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