单选题 Across the rich world, well-educated people increasingly work longer than the less-skilled. Some 65%of American men aged 62-74 with a professional degree are in the workforce, compared with 32% of men with only a high-school certificate. This gap is part of a deepening divide between the well-educated well-off and the unskilled poor. Rapid technological advance has raised the incomes of the highly skilled while squeezing those of the unskilled. The consequences, for individuals and society, are profound. The world is facing an astonishing rise in the number of old people, and they will live longer than ever before. Over the next 20 years the global population of those aged 65 or more will almost double, from 600 million to 1.1 billion. The experience of the 20th century, when greater longevity (长寿) translated into more years in retirement rather than more years at work, has persuaded many observers that this shift will lead to slower economic growth, while the swelling ranks of pensioners will create government budget problems. But the notion of a sharp division between the working young and the idle old misses a new trend, the growing gap between the skilled and the unskilled. Employment rates are falling among younger unskilled people, whereas older skilled folk are working longer. The divide is most extreme in America, where well-educated baby-boomers(二战后生育高峰期出生的美国人)are putting off retirement while many less-skilled younger people have dropped out of the workforce. Policy is partly responsible. Many European governments have abandoned policies that used to encourage people to retire early. Rising life expectancy (预期寿命), combined with the replacement of generous defined-benefit pension plans with less generous defined-contribution ones, means that even the better-off must work longer to have a comfortable retirement. But the changing nature of work also plays a big role. Pay has risen sharply for the highly educated, and those people continue to reap rich rewards into old age because these days the educated elderly are more productive than the preceding generation.Technological change may well reinforce that shift: the skills that complement computers, from management know how to creativity, do not necessarily decline with age.

单选题______ American universities produce great research and great graduate programs, they sometimes pay little attention to the teaching of undergraduate students. A. When B. While C. As D. Since

单选题Any student who ______ his homework is unlikely to pass his examination.

单选题Which of the following is not one of the differences between this generation and the past generations as far as marriage is concerned?

单选题Lincoln, former president of the United States, is a Uconspicuous/U example of a poor boy who succeeded.

单选题Classes will cease to exist by the time communism ______ throughout the world.

单选题A number of children with special educational needs are home educated when schools cannot meettheir needs.As a parent,you must make sure that your child receives a full-time education suitable to thei

单选题 GPS A The Global Positioning System is a space-based triangulation system using satellites and computers to measure positions anywhere on earth. It is first and foremost a defense system developed by the United States Department of Defense, and is referred to as the 'Navigation Satellite Timing and Ranging Global Positioning System' or NAVSTAR GPS. The uniqueness of this navigational system is that it avoids the limitations of other land-based systems such as limited geographic coverage, lack of continuous 24-hour coverage, and the limited accuracies of other related navigational instruments. The high accuracies obtainable with the Global Positioning System also make it a precision survey instrument. GPS Components: the Space Segment, the Control Segment, and the User Segment. B The Space Segment of the system consists of the GPS satellites. These space vehicles (SVs) send radio signals from space. The GPS Operational Constellation consists of 24 satellites that orbit the earth in 12 hours. There are often more than 24 operational satellites as new ones are launched to replace older satellites. The satellite orbits repeat almost the same ground track (as the earth turns beneath them) once each day. The orbit altitude is such that the satellites repeat the same track and area over any point approximately each 24 hours (4 minutes earlier each day). There are six orbital planes (with four SVs in each), equally spaced (60 degrees apart), and inclined at about fifty-five degrees with respect to the equatorial (赤道的) plane. This constellation provides the user with between five and eight SVs visible from any point on the earth. C The Control Segment consists of a system of tracking stations located around the world. The Master Control facility is located at Schriever Air Force Base (formerly Falcon AFB) in Colorado. These monitor stations measure signals from the SVs which are incorporated into orbital models for each satellites. The models compute precise orbital data and SV clock corrections for each satellite. The Master Control station uploads orbital data and clock data to the SVs. The SVs then send subsets of the orbital ephemeris (星历表) data to GPS receivers over radio signals. D The GPS User Segment consists of the GPS receivers and the user community. GPS receivers change SV signals into position, speed, and time estimates. Four satellites are required to compute the four dimensions of X, Y, Z (position) and Time. GPS receivers are used for navigation, positioning, time distribution, and other research. Navigation in three dimensions is the primary function of GPS. Navigation receivers are made for aircraft, ships, ground vehicles, and for hand carrying by individuals. Precise positioning is possible using GPS receivers at reference locations providing corrections and relative positioning data for remote receivers. Surveying, geodetic control, and plate tectonic studies are examples. E Time and frequency distribution, based on the precise clocks on board the SVs and controlled by the monitor stations, is another use for GPS. Astronomical observatories, telecommunications facilities, and laboratory standards can be set to precise time signals or controlled to accurate frequencies by special purpose GPS receivers. Research projects have used GPS signals to measure atmospheric parameters. F At present the system consists of 24 satellites at an altitude of about 20,000 km having an orbital inclination of 55 degrees. The orbits are almost circular and it takes 12 hours for a satellite to complete a pass around the Earth. GPS signals are broadcast from a cluster of 24 or more earth orbiting satellites. Because the GPS signals are derived from the atomic frequency standards on board each satellite, they are widely used as a reference for time synchronization and frequency adjustment. The real time positioning accuracy of a single receiver is normally up to 100 meters horizontally and 150 meters vertically. However, various methods have been developed which enable much higher accuracy (centimeter level). G There are a variety of different types of GPS receivers on the market for commercial and public use. Prices range from $500 to $30,000, reflecting the accuracy and capabilities of the instruments. For the general outdoorsman, a good GPS receiver should have 8 satellite tracking capability and be capable of receiving the GPS satellite signals through forest covering in northern Ontario shield area; for the professional user, a minimum 8 satellite tracking capability, high memory capacity, differential GPS capability, and resistance to signal weakening under forest covering is essential; for the professional surveyor requiring high level precision and accuracy capability, they should assess the project or application for which the technology is to be used with the help of an unbiased consultant, in order to determine the most cost effective and appropriate instrument. H Small hand held navigational units at relatively low cost allow boaters and hikers to know their position within a few hundred meters. This accuracy is sufficient for recreational use. A hand held or similar mapping unit at mid-range price that is linked to a fixed broadcast base station. These units allow utility companies, municipalities and others to locate various items (telephone poles, waterlines, valves) with a positional tolerance of several meters. This is suitable for some Geographical Information Systems (GIS) mapping purposes. I GPS technology offers numerous benefits to law enforcement agencies of all types. For some agencies, the navigational capabilities offered by GPS enhance efficiency and safety. These navigational applications can be used to support a variety of policing and criminal justice functions. Other agencies use GPS positioning technologies to carry out special operations or to provide enhanced personnel safety. For example, using computerized maps of their rights given by law, cooperated with GPS, aviation personnel can determine location, speed and time. J The positioning capabilities offered by GPS may also contribute to the success of specialized law enforcement operations such as in controlling vehicles. One such program operated in Minneapolis led to a 60% reduction in auto theft after only one month. The automatic vehicle location systems can not only provide efficiency of response and help ensure officer safety, but also provide officer with accurate information concerning the best response route to an incident. What's more, they can provide officers information that allows the closest patrol officers to be dispatched to a particular incident. K Advanced Transportation Management Systems (ATMS) are heavily dependant upon GPS technology to provide data about the road system. GPS allows for law enforcement personnel to clear roadway blockages to ensure the safety of motorist. Most people associate law enforcement with the prevention, reduction, and prosecution of criminal activity. In fact, a large portion of local law enforcement resources are involved in facilitating the movement of people and vehicles in a safe manner. In conclusion, large-volume commercial applications such as cellular phones, personal communication systems, and in-vehicle navigation systems will fuel continued development of these technologies. What was ultimately the domain of the Department of Defense is rapidly becoming available for business, private, and general government use. Policing and public safety in general, will benefit from these market forces. It is clear that there are a number of GPS applications for policing.

单选题下面的短文后列出了10个句子，请根据短文的内容对每个句子作出判断：如果该句提供的是正确信息，选择A；如果该句提供的是错误信息，选择B；如果该句的信息文中没有提及，选择C。在答题卡相应位置上将答案选项涂黑。A Female Kenyan Wine Producer　　Mrs.Karanja is the founder of the only large-scale brewery 酿酒厂 in K

单选题The premier ______ Beijing on January 2,2002. ( )

单选题Occasionally I read a passage or sentence over and over just to let the beauty of its construction ______ in.

单选题The car was repaired but not quite to my______.

单选题We made plans for a visit, but ______ difficulties with ear prevented it.

单选题Today we'll discuss proposals ______ the improvement of quality. All other proposals will be left to the next meeting. A. similar to B. relevant to C. familiar with D. regarded as

单选题Most personal managers agree that job interviews are one of the least objective recruitment methods. But the advantages of testing are not going to change the attraction of the interview to employers. The appeal of the interview has everything to do with the human factor. Most people believe that they are a reasonable judge of character and trust their instinctive feelings. We might use some kind of test to aid the selection process, but we usually pick a candidate who interviews well, has good qualifications and an impressive work record. But suppose the candidate lies or is less than completely honest, "This can be a serious problem of employers," examine Alan Conrad, Chief Executive at Optimus Recruitment. "The most difficult liars to find are those who tell half-truths rather than complete lies." Research shows that up to 75 percent of resumes are inaccurate on purpose. The most common practice is omission. Interviewer should therefore concentrate on areas of uncertainty such as gaps between periods of employment and job descriptions that seem strange. "Focusing on these areas will force candidates to tell the truth or become increasinglydishonest. This is usually when people signal their anxiety by their body language. Sweat on the upper lip, false smiles and nervous hand movements all indicate discomfort." Conrad does not suggest an aggressive policy—style interview technique, but insists that close inspection of a resume is absolutely essential. Only by asking the right questions can you confirm the suitability of the candidate or put pressure on those who are being less than completely honest.

单选题Mary always ______things over with her parents before she makes an important decision.

单选题 To many observers, he spent his wealth lavishly.

单选题She showed him the photo she ______ the day before. ( )

单选题A ______ to this problem is expected to be found before long. A. result B. response C. settlement D. solution

单选题If he ______the job, he will get more money right away.