单选题The pilot of the plane which flies faster than sound travels does not hear the thunderclaps because______.A the sound of plane engine travels slower than the planeB the frequency of the sound altersC the passage does not mention itD the pressure decreased when the plane flies in the air

考题 Hardly _______ people ran toward it. (A) the plane had landed when(B) had the plane landed when(C) the plane had landed than(D) had the plane landed than

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考题 29． When it thunders, we always see the light before we hear the sound．______ It’s becauseA． our eyes are in front of our earsB． our eyes are cleverer than our earsC． our eyes can see but our ears can-tD．light goes faster than sound

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考题 A ( )is a person who travels by train, plane or bus. A、visitorB、strangerC、patientD、passenger

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考题 A user’s laptop does not produce sound even though the volume settings are at maximum in theoperating system. Which of the following would MOST likely resolve this issue?() A. A new sound cardB. A new speakerC. A BIOS updateD. A hardware volume control

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考题 Concerning the identification signal for a pilot vessel, in fog, which statement is TRUE?___.A.When at anchor, the pilot vessel is only required to sound anchor signalsB.The identification signal must be sounded any time the pilot vessel is underwayC.The pilot vessel may only sound the identity signal when making wayD.All of the above

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考题 Text3 NASA has hired airplane manufacturer Lockheed Martin to build its next experimental plane,which is designed to fly faster than the speed of sound without producing the loud sonic booms that have plagued the transportation form.The plane is due to be delivered in 2021 and will cost just shy of$250 million.During a press conference hosted by the agency during which they announced the partnership,Lockheed Martin spokesperson Dave Richardson explained that the new plane will be neither a prototype for a new commercial airplane,nor a reincamation of previous supersonic jets."This is a purpose-built experimental research craft,"he said."This aircraft was designed from a clean sheet."NASA will use the plane to gather data about the impact ofits low-boom design,which the agency hopes will address the single biggest challenge of supersonic flight.Flying faster than the speed of sound produces shock waves that result in a loud booming sound."The air does not know that the airplane is coming,"Peter Coen,a NASA project manager for supersonic technology,explained during the press conference,Because no one liked hearing that noise,the Federal Aviation Administration and similar international organizations banned supersonic travel over land,Now,NASA thinks technology can break the sound barrier without being quite so loud about it.The secret is in the shape of the plane.Sonic booms form because the plane's flight produces many shock waves of different strengths headed in different directions that absorb into each other to create two strong pulses of pressure.From the testing done so far,NASA thinks the new plane's design successfully dissipates and weakens those shock waves,keeping them from forming the strong pulses responsible for booms.The plane would still produce what they've dubbed"sonic thumps,"but the hope is that those would be much easier to deal with.Once the new plane is built,NASA will run surveys on the ground to see how people respond to the sonic thumps.Then,the agency will bring that survey data to the Federal Aviation Administration and its intemational counterparts in order to revisit the rule about breaking the speed of sound over land."It's not about making a new airplane for airplanes'sake,although I love airplanes,"Richardson said."It's about the data that will be collected."If the rule change does come through,that could kick off a new era of commercial supersonic travel.32.The crucial factor in the sound barrier breaking technology isA.how to create the strong pulses of pressure. B.how to shape the experimental plane. C.how to run the surveys mentioned. D.how to produce the sonic thumps.

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考题 Text3 NASA has hired airplane manufacturer Lockheed Martin to build its next experimental plane,which is designed to fly faster than the speed of sound without producing the loud sonic booms that have plagued the transportation form.The plane is due to be delivered in 2021 and will cost just shy of$250 million.During a press conference hosted by the agency during which they announced the partnership,Lockheed Martin spokesperson Dave Richardson explained that the new plane will be neither a prototype for a new commercial airplane,nor a reincamation of previous supersonic jets."This is a purpose-built experimental research craft,"he said."This aircraft was designed from a clean sheet."NASA will use the plane to gather data about the impact ofits low-boom design,which the agency hopes will address the single biggest challenge of supersonic flight.Flying faster than the speed of sound produces shock waves that result in a loud booming sound."The air does not know that the airplane is coming,"Peter Coen,a NASA project manager for supersonic technology,explained during the press conference,Because no one liked hearing that noise,the Federal Aviation Administration and similar international organizations banned supersonic travel over land,Now,NASA thinks technology can break the sound barrier without being quite so loud about it.The secret is in the shape of the plane.Sonic booms form because the plane's flight produces many shock waves of different strengths headed in different directions that absorb into each other to create two strong pulses of pressure.From the testing done so far,NASA thinks the new plane's design successfully dissipates and weakens those shock waves,keeping them from forming the strong pulses responsible for booms.The plane would still produce what they've dubbed"sonic thumps,"but the hope is that those would be much easier to deal with.Once the new plane is built,NASA will run surveys on the ground to see how people respond to the sonic thumps.Then,the agency will bring that survey data to the Federal Aviation Administration and its intemational counterparts in order to revisit the rule about breaking the speed of sound over land."It's not about making a new airplane for airplanes'sake,although I love airplanes,"Richardson said."It's about the data that will be collected."If the rule change does come through,that could kick off a new era of commercial supersonic travel.33.Sonic booms result fromA.the shape ofplane. B.the sonic thumps. C.the strong pulses. D.the sound barrier.

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考题 Text3 NASA has hired airplane manufacturer Lockheed Martin to build its next experimental plane,which is designed to fly faster than the speed of sound without producing the loud sonic booms that have plagued the transportation form.The plane is due to be delivered in 2021 and will cost just shy of$250 million.During a press conference hosted by the agency during which they announced the partnership,Lockheed Martin spokesperson Dave Richardson explained that the new plane will be neither a prototype for a new commercial airplane,nor a reincamation of previous supersonic jets."This is a purpose-built experimental research craft,"he said."This aircraft was designed from a clean sheet."NASA will use the plane to gather data about the impact ofits low-boom design,which the agency hopes will address the single biggest challenge of supersonic flight.Flying faster than the speed of sound produces shock waves that result in a loud booming sound."The air does not know that the airplane is coming,"Peter Coen,a NASA project manager for supersonic technology,explained during the press conference,Because no one liked hearing that noise,the Federal Aviation Administration and similar international organizations banned supersonic travel over land,Now,NASA thinks technology can break the sound barrier without being quite so loud about it.The secret is in the shape of the plane.Sonic booms form because the plane's flight produces many shock waves of different strengths headed in different directions that absorb into each other to create two strong pulses of pressure.From the testing done so far,NASA thinks the new plane's design successfully dissipates and weakens those shock waves,keeping them from forming the strong pulses responsible for booms.The plane would still produce what they've dubbed"sonic thumps,"but the hope is that those would be much easier to deal with.Once the new plane is built,NASA will run surveys on the ground to see how people respond to the sonic thumps.Then,the agency will bring that survey data to the Federal Aviation Administration and its intemational counterparts in order to revisit the rule about breaking the speed of sound over land."It's not about making a new airplane for airplanes'sake,although I love airplanes,"Richardson said."It's about the data that will be collected."If the rule change does come through,that could kick off a new era of commercial supersonic travel.31.According to the first two paragraphs,the experimental planeA.will need an exact budget of$250 million. B.will be put into service in 2021. C.is designed from an entirely new angle. D.is based on a new commercial purpose.

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考题 Text3 NASA has hired airplane manufacturer Lockheed Martin to build its next experimental plane,which is designed to fly faster than the speed of sound without producing the loud sonic booms that have plagued the transportation form.The plane is due to be delivered in 2021 and will cost just shy of$250 million.During a press conference hosted by the agency during which they announced the partnership,Lockheed Martin spokesperson Dave Richardson explained that the new plane will be neither a prototype for a new commercial airplane,nor a reincamation of previous supersonic jets."This is a purpose-built experimental research craft,"he said."This aircraft was designed from a clean sheet."NASA will use the plane to gather data about the impact ofits low-boom design,which the agency hopes will address the single biggest challenge of supersonic flight.Flying faster than the speed of sound produces shock waves that result in a loud booming sound."The air does not know that the airplane is coming,"Peter Coen,a NASA project manager for supersonic technology,explained during the press conference,Because no one liked hearing that noise,the Federal Aviation Administration and similar international organizations banned supersonic travel over land,Now,NASA thinks technology can break the sound barrier without being quite so loud about it.The secret is in the shape of the plane.Sonic booms form because the plane's flight produces many shock waves of different strengths headed in different directions that absorb into each other to create two strong pulses of pressure.From the testing done so far,NASA thinks the new plane's design successfully dissipates and weakens those shock waves,keeping them from forming the strong pulses responsible for booms.The plane would still produce what they've dubbed"sonic thumps,"but the hope is that those would be much easier to deal with.Once the new plane is built,NASA will run surveys on the ground to see how people respond to the sonic thumps.Then,the agency will bring that survey data to the Federal Aviation Administration and its intemational counterparts in order to revisit the rule about breaking the speed of sound over land."It's not about making a new airplane for airplanes'sake,although I love airplanes,"Richardson said."It's about the data that will be collected."If the rule change does come through,that could kick off a new era of commercial supersonic travel.35.In the eyes of the author,the new plane isA.promising. B.premium. C.speedy. D.risky.

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考题共用题干第二篇The Magic of SoundMusic is one of the most beautiful forms of artistic expressions ever invented.In movies and plays, music has an added function:it not only moves people but also can shock people.Our eardrums can withstand sound within 20 to 80 decibels（分贝）.Once sound exceeds this limit , even beautiful music will become ear-splitting noise and harm health.A strong blast（响声）of high sound can twist and break a solid iron sheet.High sound of 150 decibels can kill a healthy rat.In movies,sometimes the hero can produce a sound that ordinary people can't hear and only those whohave the same ability can feel.In nature,there is actually sound that is beyond our hearing.In physics,the sound that exceeds 20,000Hz is called ultrasonic（超音波的）.Dolphins, whales and bats can make such high-frequency sound.It does no harm to health.Sound less than 20Hz is called infrasonic（次声）waves.When we move, the air will vibrate.The vibration of air can produce infrasonic waves.As the frequency of infrasonic waves is close to that of people's internal organs, infrasonic wave may cause resonance（共振）in human bodies.As a result,people's vision may weaken and internal organs may rupture（断裂）.However,whether an infrasonic wave can be used as a weapon depends on its intensity.If its intensity is very low,it won't damage internal organs or a person's health.If the intensity of infrasonic wave exceeds 160 decibels,it is extremely harmful.When wind blows at a force of 3 or 4 over the sea,it will produce infrasonic waves of several decibels.Only typhoons can produce infrasonic waves of over 100 decibels.At present,scientists can only produce infrasonic weapons in the lab with the help of advanced scientific tools and powerful electric power.An ultrasonic sound______.A:is very loudB:does harm to people's healthC:cannot be heard by peopleD:is produced by the hero in movies

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考题共用题干第二篇The Magic of SoundMusic is one of the most beautiful forms of artistic expressions ever invented.In movies and plays, music has an added function:it not only moves people but also can shock people.Our eardrums can withstand sound within 20 to 80 decibels（分贝）.Once sound exceeds this limit , even beautiful music will become ear-splitting noise and harm health.A strong blast（响声）of high sound can twist and break a solid iron sheet.High sound of 150 decibels can kill a healthy rat.In movies,sometimes the hero can produce a sound that ordinary people can't hear and only those whohave the same ability can feel.In nature,there is actually sound that is beyond our hearing.In physics,the sound that exceeds 20,000Hz is called ultrasonic（超音波的）.Dolphins, whales and bats can make such high-frequency sound.It does no harm to health.Sound less than 20Hz is called infrasonic（次声）waves.When we move, the air will vibrate.The vibration of air can produce infrasonic waves.As the frequency of infrasonic waves is close to that of people's internal organs, infrasonic wave may cause resonance（共振）in human bodies.As a result,people's vision may weaken and internal organs may rupture（断裂）.However,whether an infrasonic wave can be used as a weapon depends on its intensity.If its intensity is very low,it won't damage internal organs or a person's health.If the intensity of infrasonic wave exceeds 160 decibels,it is extremely harmful.When wind blows at a force of 3 or 4 over the sea,it will produce infrasonic waves of several decibels.Only typhoons can produce infrasonic waves of over 100 decibels.At present,scientists can only produce infrasonic weapons in the lab with the help of advanced scientific tools and powerful electric power.What could be the best title of the passage?A:The power of music.B:The harms of noises.C:The magic of sound.D:The discovery of infrasonic waves.

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考题共用题干第二篇The Magic of SoundMusic is one of the most beautiful forms of artistic expressions ever invented.In movies and plays, music has an added function:it not only moves people but also can shock people.Our eardrums can withstand sound within 20 to 80 decibels（分贝）.Once sound exceeds this limit , even beautiful music will become ear-splitting noise and harm health.A strong blast（响声）of high sound can twist and break a solid iron sheet.High sound of 150 decibels can kill a healthy rat.In movies,sometimes the hero can produce a sound that ordinary people can't hear and only those whohave the same ability can feel.In nature,there is actually sound that is beyond our hearing.In physics,the sound that exceeds 20,000Hz is called ultrasonic（超音波的）.Dolphins, whales and bats can make such high-frequency sound.It does no harm to health.Sound less than 20Hz is called infrasonic（次声）waves.When we move, the air will vibrate.The vibration of air can produce infrasonic waves.As the frequency of infrasonic waves is close to that of people's internal organs, infrasonic wave may cause resonance（共振）in human bodies.As a result,people's vision may weaken and internal organs may rupture（断裂）.However,whether an infrasonic wave can be used as a weapon depends on its intensity.If its intensity is very low,it won't damage internal organs or a person's health.If the intensity of infrasonic wave exceeds 160 decibels,it is extremely harmful.When wind blows at a force of 3 or 4 over the sea,it will produce infrasonic waves of several decibels.Only typhoons can produce infrasonic waves of over 100 decibels.At present,scientists can only produce infrasonic weapons in the lab with the help of advanced scientific tools and powerful electric power.What does the author say about music?A:It may be harmful to people's health.B:It always cheers people up.C:It is very often difficult to understand.D:It sounds better when it is loud enough.

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考题 Which of the following is a disadvantage of using the EIGRP protocol?（）A、It does not scale wellB、It converges slower than OSPFC、It is a proprietary protocolD、It is a distance vector protocol

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考题 A user’s laptop does not produce sound even though the volume settings are at maximum in theoperating system. Which of the following would MOST likely resolve this issue?（）A、A new sound cardB、A new speakerC、A BIOS updateD、A hardware volume control

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考题单选题A user’s laptop does not produce sound even though the volume settings are at maximum in theoperating system. Which of the following would MOST likely resolve this issue?（）A A new sound cardB A new speakerC A BIOS updateD A hardware volume control

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考题单选题As the plane flew off towards the mountains in the distance the sound of its engines gradually ______.A died awayB sank down C dropped offD went out

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考题填空题Because light travels (fast) ____ than sound, lightning is seen before thunder(雷) is heard.

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考题单选题A refrigerant with oil in solution has a （）.A higher boiling temperature for a given pressure than does a pure refrigerantB lower boiling temperature for a given pressure than does a pure refrigerantC boiling pressure equal to that of a pure refrigerant at a given pressureD boiling point will not be affected by entrained oil

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考题单选题Decibel is______.A the unit for measuring the intensity of soundB the pressure of radiating wavesC the frequency of radiating wavesD the seed of sound

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考题单选题Sound is audible to human beings only if the frequency is______.A fewer than about 20 vibrations per secondB more than about 20,000 vibrations per secondC about in a range of 20 to 20,000 vibrations per secondD 120 vibrations per second

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考题单选题Which of the following is a disadvantage of using the EIGRP protocol?（）A It does not scale wellB It converges slower than OSPFC It is a proprietary protocolD It is a distance vector protocol

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考题单选题Concerning the identification signal for a pilot vessel，in fog，which statement is TRUE?（）A When at anchor，the pilot vessel is only required to sound anchor signalsB The identification signal must be sounded any time the pilot vessel is underwayC The pilot vessel may only sound the identity signal when making wayD All of the above

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考题单选题We see lightning before we hear the thunder because sound travels more slowly than light is.A before weB becauseC more slowlyD light is

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考题填空题What kind of sound does the mouse produce?It produces ____ sounds.

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考题单选题Which of the following shows the normal hearing process of a mother hearing her baby crying?a. The ears receive the sound waves.b. The mother recognizes her baby’s cry.c. The ears turn the sound waves into signals.d. The baby’s cry travels in the form of sound waves.e. The brain connects the signals to the information in the memory.A d-a-c-b-eB d-a-c-e-bC a-d-c-b-eD a-d-c-e-b

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考题单选题Which of the following can serve as the best title of this passage?A The Prefix Mach.B The Speed of Sound.C The Frequency of Sound.D The Intensity of Sound.

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考题单选题It is implied by the writer that _____.A it is cheaper to travel by plane than by trainB the railway station is usually in the suburb of the cityC when you get off the plane you will find yourself in the center of the cityD no motorcar or plane can carry as much goods as a train does

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