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— Space travel must be very very expensive.
— . The cost of a seat on the Virgin craft is $ 250,000.
A、That’s not true.
B、Of course.
C、Why do you think so？
答案
更多“— Space travel must be very very expensive.— . The cost of a seat on the Virgin craft is”相关的问题
第1题
We believe, however, that some two thousand million years ago, another star wandering through space, happened to come near our sun. Just as the sun and the moon raise tides on the earth, so this star must have raised tides on the surface of the sun. But they were very different from the small tides that are raised in our oceans; a large tidal wave' must have travelled over the surface of the sun, at last forming a mountain so high that we cannot imagine it. As the cause of the disturbance (动荡) came nearer, so the mountain rose higher and higher. And before the star began to move away again, its tidal pull had become so powerful that this mountain was torn to pieces and threw off small parts of itself into space. These small pieces have been going round the sun ever since. They are the planets (行星).
Millions of stars are______.
A．following a regular path in space
B．always travelling together
C．seldom wandering about in the universe
D．moving about without a fixed course
第2题
A.short
B.scarce
C.rare
D.unexpected
第3题
A.The cylinders must be stowed at least 10 horizontal feet from corrosive materials in the same space
B.Stowage in the upper deck-deck is considered to be the equivalent of "on deck" stowage for this cargo
C.The cylinders must have a red label for flammability and a green label for compressed gas
D.The cylinders may be protected from the radiant heat of the Sun by laying a tarp on them
第4题
Although trains were a popular means of travel for some time, automobiles slowly began to take their place. Automobile travel caused problems for city hotels, which did not have enough parking space for so many cars.
People who traveled by automobile needed a different kind of hotel. They needed places to stay that were near highways and had room to park. Motorists did not like to drive in heavy city traffic to reach a hotel. The answer to the motorists' problems came when a new kind of hotel was built. These new buildings were called motels, a word made from the first part of MOTORIST and the last part of HOTELS.
Motels were much smaller than hotels. Built on ground level, often in separate units, they were more convenient for people traveling. The separate units also made them quieter than hotels, best of all, there was more than enough room for cars to park. ,
Now, many big hotels in the cities are being torn down. They can no longer make enough money to stay in business. In their place, many small motels have been built on the outskirts(近郊) of cities. Motels have become a big business in the United States.
The first hotels were built______.
A．with hundreds of rooms
B．around the city centers
C．near railway stations
D．quite close to roads.
第5题
A sound is a pressure disturbance: a sonic boom, like other explosive sounds, is the result of an abrupt change in pressure. An airplane in subsonic flight produces weak changed in pressure, but because these disturbances travel at the speed of sound, they move faster than the airplane and stay in front of it. In effect, these disturbances warn the air to get out of the way, and the an does just jet, however, gets ahead of its own pressure disturbances. Consequently a wave of suddenly com pressed air--a shock wave--builds up and is thrown off like the wave ;hat spreads from the bow of a speedboat.
Can sonic booms be eliminated？ The answer is a categorical negative--they are an innerent(内在的) part of supersonic flight--but the sonic boom probably can be reduced; government and private research is now under way to improve understanding of the sonic boom. If and when the booms can be reduced to tolerable levels, commercial supersonic transports can come rata service.
Before commercial airliners travel faster than sound, problems must 0e solved regarding ______.
A．design
B．Construction
C．operation
D．all of the above
第6题
There are some good ideas to reduce the use of private cars. In 1989, for example, the authorities in Rome began an interesting experiment: passengers on the city buses did not have to pay for their tickets.
In Stockholm there was another experiment: people paid very little for a season ticket to travel on any bus, trolley bus, train or tram in all the city.
In many cities now some streets are closed to vehicles, and pedestrians are safe there.
In London there is another experiment: part of the street is for buses only, so the buses can travel fast. There are no cars or taxies in front of them.
What the writer worries about in a big city is ______.
A．the number of traffic lights
B．the shortage of buses
C．the lack of motorways
D．the traffic congestion
第7题
In a plan called “Station Renaissance” that it__3__in November, JR East said that it would__4__using its commercial spaces for shops and restaurants, extending them to__5__more suitable for the information age. It wants train stations as pick-up__6__for such goods as books, flowers and groceries__7__over the Internet. In a country where city__8__depend heavily on trains__9__commuting, about 16 million people a day go to its train stations anyway, the company __10__. So, picking up commodities at train stations__11__consumers extra travel and missed home deliveries. JR East already has been using its station__12__stores for this purpose, but it plans to create__13__spaces for the delivery of Internet goods.
The company also plans to introduce __14__cards—known in Japan as IC cards because they use integrated circuit for__15__information__16__ train tickets and commuter passes__17__the magnetic ones used today, integrating them into a/an __18__pass. This will save the company money, because__19__for IC cards are much less expensive than magnetic systems. Increased use of IC cards should also__20__the space needed for ticket vending.
A.perspectives
B.outlooks
C.prospects
D.spectacles
第8题
A.way
B.answer
C.help
D.means
第9题
No longer is the possession of information【C11】______ to a privileged minority. Forty years ago people used to【C12】______ to the cinema, but now far more people sit at home and turn on the TV to watch a programme that【C13】______ into millions of homes. Communication is no longer merely concerned【C14】______ the transmission of information. The modem communications industry influences the way people live in society and broadens, their【C15】______ by allowing access to information, education and entertainment. The printing, broadcasting and【C16】______ industries are all involved with informing, educating and entertaining.
【C17】______ a great deal of the material communicated by the mass media is very【C18】______ to the individual and to the society of which he is a part, the vast modem network of communications is【C19】______ to abuse. How ever, the mass media are with us for better, for worse, and there is no turning【C20】______ .
【C1】
A．basis
B．base
C．foundation
D．ground
第10题
national holiday that has been arranged to be celebrated on a Monday. The holidays have all been decided to be celebrated on a Monday so that the workers may have 3-day weekends—that is？ Saturday？ Sunday and Monday in order to rest or travel or do things with their families. Major holidays in the United States such as New Year’s Day or Christmas Day or the day？ when we remember the first settlers of the United States？ called Thanksgiving Day are celebrated all over the country. During these holidays most businesses close and the workers stay home and celebrate with their families.
Vacation can be from 2 weeks a year to 4 weeks a year. This usually depends on how long you’ve been working for a company？ what type of position you have？ whether you have a very high position or a very important position and it’s difficult to find someone to replace you. In this case？ you might take a few days at a time rather than taking one month all at once. Usually the more time you spend working for a company？ the more time you may get for a vacation.
1.The government of the United States makes it a rule for workers to have a ____weekend almost once a month.
A.5-day
B.2-day
C.3-day
D.4-day
2.Workers in the United States sometimes work from.（）
A.Monday to Saturday
B.Tuesday to Sunday
C.Thursday to Friday
D.Tuesday to Friday
3.Which statement is NOT true according to this passage？（）
A.Only a few shops remain open on New Year’s Day
B.Most of the workers needn’t work on Christmas Day
C.Days on vacation must be more than all the holidays in a year
D.All the workers have a half-month vacation
4.The reason why someone has to divide his vacation into several parts is that ().
A.no one can be found to take his place
B.he hasn’t a most high position
C.he plays an important role in his work
D.he hasn’t been working for his company for a long time
5. Which of the following is the best title for this passage？（）
A.Holidays in the United States
B.Vacation in the United States
C.How Do the Workers Spend Their Holidays
D.Something About the Holidays and Vacation in the U.S
第11题
看资料，回答题
The Impossibility of Rapid Energy Transitions
[ A ] Politicians are fond of promising rapid energy transitions．Whether it is a transition from imported to domestic oil or from coal-powered electricity production to natural-gas power plants， politicians love to talk big．Unfortunately for them （and often the taxpayers）， our energy systems are a bit like an aircraft carrier: they are unbelievably expensive， they are built to last for a very long time， they have a huge amount of inertia （meaning it takes a lot of energy to set them moving ）， and they have a lot of momentum once they are set in motion．No matter how hard you try， you can"t turn something that large on a dime （10美分硬币 ）， or even a few thousand dimes．
[ B ] In physics， moving objects have two characteristics relevant to understanding the dynamics of energy systems: inertia and momentum．Inertia is the resistance of objects to efforts to change their state of motion．If you try to push a boulder （大圆石 ）， it pushes you back．Once you have started the boulder rolling， it develops momentum， which is defined by its mass and velocity．Momentum is said to be "conserved，" that is， once you build it up， it has to go somewhere．So a heavy object， like a football player moving at a high speed， has a lot of momentum-that is， once he is moving， it is hard to change his state of motion．If you want to change his course， you have only a few choices: you can stop him， transferring （possibly painfully） some of his kinetic energy （动能） to your own body， or you can approach alongside and slowly apply pressure to gradually alter his course．
[ C ] But there are other kinds of momentum as well．After all， we don"t speak only of objects or people as having momentum; we speak of entire systems having momentum．Whether it"s a sports team or a presidential campaign， everybody relishes having the big momentum， because it makes them harder to stop or change direction．
[ D ] One kind of momentum is technological momentum．When a technology is deployed， its impacts reach far beyond itself．Consider the incandescent （白炽灯的） bulb， an object currently hated by many environmentalists and energy-efficiency advocates．The incandescent light bulb， invented by Thomas Edison， which came to be the symbol of inspiration， has been developed into hundreds， if not thousands， of forms．Today， a visit to a lighting store reveals a stunning array of choices．There are standard-shaped bulbs， flame-shaped bulbs， colored globe-shaped bulbs， and more．It is quite easy， with all that choice， to change a light bulb．
[ E ] But the momentum of incandescent lighting does not stop there．All of those specialized bulbs ledto the building of specialized light fixtures， from the desk lamp you study by， to the ugly but beloved hand-painted Chinese lamp you inherited from your grandmother， to the ceiling fixture in your closet， to the light in your oven or refrigerator， and to the light that the dentist points at you．It is easy to change a light bulb， sure， but it is harder to change the bulb and its fixture．
[ F ] And there is more to the story， because not only are the devices that house incandescent bulbs shaped to their underlying characteristics， but rooms and entire buildings have been designed in accordance with how incandescent lighting reflects off walls and windows．
[ G ] As lighting expert Howard Brandston points out， “ Generally， there are no bad light sources， only bad applications．" There are some very commendable characteristics of the CFL [ compact fluorescent （荧光的） light bulb ]， yet the selection of any light source remains inseparable from the luminaire （照明装置 ） that houses it， along with the space in which both are installed， and lighting requirements that need to be satisfied．The lamp， the fixture， and the room， all three must work in concert for the true benefits of end-users．If the CFL should be used for lighting a particular space， or an object within that space， the fixture must be designed to work with that lamp， and that fixture with the room．It is a symbiotic （共生的 ） relationship．A CFL cannot be simply installed in an incandescent fixture and then expected to produce a visual appearance that is more than washed out， foggy， and dim．The whole fixture must be replaced-light source and luminaire-and this is never an inexpensive proposition．
[ H ] And Brandston knows a thing or two about lighting， being the man who illuminated the Statue of Liberty．
[ I ]Another type of momentum we have to think about when planning for changes in our energy systems is labor-pool momentum．It is one thing to say that we are going to shift 30 percent of our electricity supply from， say， coal to nuclear power in 20 years．But it is another thing to have a supply of trained talent that could let you carry out this promise．That is because the engineers，designers， regulators， operators， and all of the other skilled people needed for the new energy industry are specialists who have to be trained first （or retrained， if they are the ones being laid off in some related industry）， and education， like any other complicated endeavor， takes time．And not only do our prospective new energy workers have to be trained， they have to be trained in the right sequence．One needs the designers， and perhaps the regulators， before the builders and operators， and each group of workers in training has to know there is work waiting beyond graduation．In some cases， colleges and universities might have to change their training programs，
adding another layer of difficulty．
[ J ] By far the biggest type of momentum that comes into play when it comes to changing our energy systems is economic momentum．The major components of our energy systems， such as fuel production， refining， electrical generation and distribution， are costly installations that have lengthy life spans．They have to operate for long periods of time before the costs of development have been recovered．When investors put up money to build， say， a nuclear power plant， they expect to earn that money back over the planned life of the plant， which is typically between 40and 60 years．Some coal power plants in the United States have operated for more than 70 years!
The oldest continuously operated commercial hydro-electric plant in the United States is on New York"s Hudson River， and it went into commercial service in 1898．
[ K ] As Vaclav Smil points out， "All the forecasts， plans， and anticipations cited above have failed so miserably because their authors and promoters thought the transitions they hoped to implement would proceed unlike all previous energy transitions， and that their progress could be accelerated in an unprecedented manner．"
[ L ] When you hear people speaking of making a rapid transition toward any type of energy， whether it is a switch from coal to nuclear power， or a switch from gasoline-powered cars to electric cars， or even a switch．from an incandescent to a fluorescent light， understanding energy system inertia and momentum can help you decide whether their plans are feasible．
Not only moving objects and people but all systems have momentum．
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