单选题The phrase “this element of the unknown” (Paragraph 3) refers to ______.A the extension of earthquake zonesB the percentage of earthquake occurrencesC when and where earthquakes may occurD what big damage earthquakes may cause

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单选题

The phrase “this element of the unknown” (Paragraph 3) refers to ______.

the extension of earthquake zones

the percentage of earthquake occurrences

when and where earthquakes may occur

what big damage earthquakes may cause

更多“单选题The phrase “this element of the unknown” (Paragraph 3) refers to ______.A the extension of earthquake zonesB the percentage of earthquake occurrencesC when and where earthquakes may occurD what big damage earthquakes may cause”相关问题

第1题

共用题干 A Great Quake Coming?Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults are places where pieces of Earth ' s crust（地壳）slide past each other. When these pieces slip , the ground shakes.To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-dict how bad the damage might be when the next one happens.One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second. During bigger quakes,however,ruptures can happen at rates faster than 3.5 kilometers per second.At such high speeds,massive amounts of pressure build up,generating underground waves that can cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled away from the city during the 1906 event.As bad as the damage was,it could have been far worse.Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data, however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62 percent.New buildings in San Francisco are quite safe in case of future quakes.Still,more than 84 percent of thecity's buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive damage.People who live there today tend to feel safe because San Francisco has remained pretty quiet for a while.According to the new research,however,it's not a matter of"if" the Big One will hit.It's just a mat- ter of when.San Francisco is fully prepared for another big earthquake.A:RightB:WrongC:Not mentioned

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第2题

共用题干第一篇How to Do with Earthquake?Ideally,people would like to know when an earthquake is going to happen and how bad it willbe.In both Japan and China,people have long believed that earthquakes can be forecast. In Japan, scientists have wired the Earth and sea to detect movements.The Chinese have traditionally watched animals and plants for warning signs of earthquakes.For example,the Chinese have noted that before an earthquake,hens' behavior changes一they refuse to enter their cages at night. They have also noticed that snakes come out of the ground to freeze to death and that dogs bark a lot,even normally quiet dogs.Before the Hanshin earthquake in Japan,there were reports of large schools of fish swimming near the surface of the water. Certain birds,like pigeons,also seemed to be especially noisy and were reported to be flying in unusual patterns before the earthquake.Perhaps most interesting,and most easily measured,is a chemical change in ground water before a quake.Experimental data seem to indicate that the amount of radon(Rn)in the water under the surface of the Earth waxes before an earthquake.People would also like to be able to prevent the great destruction of property caused by earthquakes.After all,most of the people who die in earthquakes are killed by falling buildings.Therefore,building structures that can withstand the power of earthquakes is a major concern.Steel seems to be the best material,but not if it is welded to form a rigid structure.Many new structures are built with a new type of steel joint,an I-joint,which appears to be the most durable type of joint. These joints of steel can move without breaking. Also,to prevent property damage,architects now design buildings so that the building's columns and horizontal beams are of equal strength,and vertical support columns are inserted deep into solid soil.In addition,many new houses have relatively light roofs and strong walls.Concrete pillars for highway bridges that previously only had steel rods inside are now enclosed in steel.Besides working to improve building structures,people in areas where earthquakes are common need to prepare for the possibility of a great earthquake.They should regularly check and reinforce their homes,place heavy objects in low positions,attach cupboards and cabinets to walls,and fasten doors so that they will not open accidentally during an earthquake.According to the passage,the amount of radon(Rn)in the water may______before earthquake.A:increase B:reduce C:not change D:disappear

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第3题

共用题干第一篇How to Do with Earthquake?Ideally,people would like to know when an earthquake is going to happen and how bad it willbe.In both Japan and China,people have long believed that earthquakes can be forecast. In Japan, scientists have wired the Earth and sea to detect movements.The Chinese have traditionally watched animals and plants for warning signs of earthquakes.For example,the Chinese have noted that before an earthquake,hens' behavior changes一they refuse to enter their cages at night. They have also noticed that snakes come out of the ground to freeze to death and that dogs bark a lot,even normally quiet dogs.Before the Hanshin earthquake in Japan,there were reports of large schools of fish swimming near the surface of the water. Certain birds,like pigeons,also seemed to be especially noisy and were reported to be flying in unusual patterns before the earthquake.Perhaps most interesting,and most easily measured,is a chemical change in ground water before a quake.Experimental data seem to indicate that the amount of radon(Rn)in the water under the surface of the Earth waxes before an earthquake.People would also like to be able to prevent the great destruction of property caused by earthquakes.After all,most of the people who die in earthquakes are killed by falling buildings.Therefore,building structures that can withstand the power of earthquakes is a major concern.Steel seems to be the best material,but not if it is welded to form a rigid structure.Many new structures are built with a new type of steel joint,an I-joint,which appears to be the most durable type of joint. These joints of steel can move without breaking. Also,to prevent property damage,architects now design buildings so that the building's columns and horizontal beams are of equal strength,and vertical support columns are inserted deep into solid soil.In addition,many new houses have relatively light roofs and strong walls.Concrete pillars for highway bridges that previously only had steel rods inside are now enclosed in steel.Besides working to improve building structures,people in areas where earthquakes are common need to prepare for the possibility of a great earthquake.They should regularly check and reinforce their homes,place heavy objects in low positions,attach cupboards and cabinets to walls,and fasten doors so that they will not open accidentally during an earthquake.What should people do to prepare for earthquakes?A:Check and reinforce their homes.B:Place light objects in low positions.C:Build strong roofs and light walls.D:Attach doors to walls.

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第4题

共用题干 Earthquake1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.Paragraph 2_______.A:Earthquakes forecastB:Historical records of earthquakesC:Intensities of earthquakesD:Cause of earthquakesE:Indications of earthquakes F: Damaging earthquakes

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第5题

共用题干 Earthquake1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.Earthquakes can be predicted by observing__________.A:by the quake itselfB:not be preventedC:to cause damage of property and loss of livesD:of a possible earthquakeE:the unusual behaviors of some animals F: the strange behaviors of human beings

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第6题

共用题干 Earthquake1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.Scientists have been working hard to warn people__________. A:by the quake itselfB:not be preventedC:to cause damage of property and loss of livesD:of a possible earthquakeE:the unusual behaviors of some animals F: the strange behaviors of human beings

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第7题

共用题干 Earthquake1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.Paragraph 3_________.A:Earthquakes forecastB:Historical records of earthquakesC:Intensities of earthquakesD:Cause of earthquakesE:Indications of earthquakes F: Damaging earthquakes

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单选题The phrase “this element of the unknown” (Paragraph 3) refers to ______.A the extension of earthquake zonesB the percentage of earthquake occurrencesC when and where earthquakes may occurD what big damage earthquakes may cause

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更多“单选题The phrase “this element of the unknown” (Paragraph 3) refers to ______.A the extension of earthquake zonesB the percentage of earthquake occurrencesC when and where earthquakes may occurD what big damage earthquakes may cause”相关问题

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