Longitude and Latitude The meridians of longitude are imaginary great circles drawn from pole to pole around the earth. By international agreement, the meridian of longitude passing through Greenwich, England, is numbered zero. The earth is divided into 360 degrees, and the meridians are numbered east and west from Greenwich. There are 180 degrees of longitude east of Greenwich and 180 degrees in the westerly direction. New York has a longitude of 74 degrees west (74oW.) which means that it lies on the 74th meridian west of Greenwich. Since the sun appears to travel around the earth in 24 hours, it will move 360/24 or 15 degrees in one hour. This reasoning can be used by navigators to determine their longitude. Imagine that we have set sail from Greenwich, England, after having set a very accurate clock, or chronometer, to the local Greenwich time. As we travel westward toward New York, we notice that the sun is going "slower" than our chronometer. At the time that our timepiece reads 12 o’clock, the sun has not quite reached the zenith. As a matter of fact, when our clock reads noon, what it really means is that it’s noon in Greenwich, England. Our clock continues to tell us the time, not at our present location, but at Greenwich. Let us wait until the sun is directly overhead (noon at our location) and then read the time on our clock. Suppose it reads i o’clock. This means that there is one hours difference in time between our longitude and that of Greenwich. As we mentioned earlier, this corresponds to exactly 15 degrees of longitude, so our longitude must be 150 W. The world is divided into 24 time zones, and each zone corresponds to 15 degrees of longitude. New York is approximately 5 time zones west of Greenwich, so the time difference must be about 5 hours. By maintaining chronometers on Greenwich time, ships can determine their longitude on any sunny day by merely noting the difference in hours between Greenwich time and local sun time and multiplying this difference by 15 degrees. Of course, longitude gives only half of the information needed to determine our precise location. We must also know our latitude, which tells us how far we are north or south of the Equator. The Equator is the zero line for the measurement of latitude. Circles are drawn parallel to the Equator to indicate other values of latitude. There are 90 degrees of south latitude. In the Northern Hemisphere there is a star called Polaris almost directly over the North Pole. This makes it possible to determine the latitude of a given point by setting our sextant (六分仪) to measure the angle between Polaris;the North Star, and the horizon. Mathematicians tell us that this angle is equal to the latitude at the point in question. To get idea of our location, therefore, we need to know local time, Greenwich time, and the angle between Polaris and the horizon. A navigator’s chronometer will always show _____________.
A. Greenwich time
B. noon time
C. local time
D. sun time
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某小家用电器生产企业只生产家用多功能食品粉碎机一种产品,其总成本习性模型为Y=1000000+300X。假定该企业2011年度家用多功能食品粉碎机销售量为10000台,每台售价为500元。经预测2012年对该种家用多功能食品粉碎机销售数量可以增长10%。 如果2011年发生负债利息为500000元,且企业没有优先股,计算复合杠杆系数。
A企业为生产应税消费品的企业,2008年的含税销售收入为936万元,销售利润率为15%,适用的增值税税率为17%,材料成本占总成本的百分比为65%,假定该企业生产所使用的材料都是在当期内采购的,适用的消费税税率为5%,城市维护建设税税率为7%,教育费附加的征收率为3%,发生的各项应交税金及附加均于当期以现金形式支付。2009年A企业预计的含税销售收入为1170万元,预交所得税40万元。 计算2009年预计发生的销售税金及附加。
What do you do if you don’t get into your first choice of university That’s the dilemma that faces thousands of British students every year. Many candidates turn to Clearing, the service that helps find university places for students at the last moment. If they don’t have the marks to get into their first choice of institution, Clearing tells them about places available at other universities, though they might have to read another subject. But this year has seen a record number of people applying to university. This, combined with the weak economy, an uncertain job market and budget cuts at universities, means that there’s been even more of a scramble for places than usual. Some sources say six students have applied for each remaining undergraduate university place. The British university admissions service, UCAS, says up to a quarter of this year’s university applicants—almost 190,000 people—still don’t have a place on a degree course. That’s a rise of over 46,000 students from last year. Faced with these figures, some British students might be thinking of an interesting alternative: studying abroad. The University of Nottingham, for example, is offering places at its campuses in Ningbo, near Shanghai, and Kuala Lumpur, Malaysia. Students here can gain University of Nottingham degrees in business, accounting, engineering and English. Similarly, the University of Bolton says it has "unlimited" places at its campus in the United Arab Emirates. Given the problems getting into university, the UK’s Higher Education Minister, David Willetts, encourages students who haven’t made the grade to consider alternatives to university, such as apprenticeships and studying at home. "There are a range of options available," he says. "People are able to reapply. They should think how they can spend their year adding that bit to their CV, which would help their application—getting practical work experience or extra skills—anything that strengthens their chances next year." But some commentators say that rising university costs, poor long-term job prospects, and a drop in graduate recruitment mean it’s the worst time to be a university student in the UK. It is implied in the passage that______.
A. Studying abroad should be the only choice of applicants if they can’t get any places in universities of Britain.
B. University of Nottingham at its campuses in Ningbo also accepts British students.
C. Students are not allowed to work without higher education.
D. Students are not encouraged to study at home.
Migration is usually defined as "permanent or semipermanent change of residence". This broad definition, of course, would include a move across the street or across a city. Our concern is with movement between nations, not with internal migration within nations, although such movements often exceed international movements in volume. Today, the motives of people who move short distances are very similar to those of international migrants. Students of human migration speak of "push" and "pull" factors, which influence an individual’s decision to move from one place to another. Push factors are associated with the place of origin. A push factor can be as simple and mild a matter as difficulty in finding a suitable job, or as traumatic as war, or severe famine. Obviously, refugees who leave their homes with guns pointed at their heads are motivated almost entirely by push factors (although pull factors do influence their choice of destination). Pull factors are those associated with the place of destination. Most often these are economic, such as better job opportunities or the availability of good land to farm. The latter was an important factor in attracting settlers to the United States during the 19th century. In general, pull factors add up to an apparently better chance for a good life and material well-being than is offered by the place of origin. When there is a choice between several attractive potential destinations, the deciding factor might be a noneconomic consideration such as the presence of relatives, friends, or at least fellow countrymen already established in the new place who are willing to help the newcomers settle in. Considerations of this sort lead to the development of migration flow. Besides push and pull factors, there are what the sociologists call "intervening obstacles". Even if push and/or pull factors are very strong, they still may be outweighed by intervening obstacles, such as the distance of the move, the trouble and cost of moving, the difficulty of entering the new country, and the problems likely to be encountered on arrival. The decision to move is also influenced by "personal factors" of the potential migrant. The same push-pull factors and obstacles operate differently on different people, sometimes because they are at different stages of their lives, or just because of their varying abilities and personalities. The prospect of packing up everything and moving to a new and perhaps very strange environment may appear interesting and challenging to an unmarried young man and appallingly difficult to a slightly older man with a wife and small kids. Similarly, the need to learn a new language and customs may excite one person and frighten another. Regardless of why people move, migration of large numbers of people causes conflict. The United States and other Western countries have experienced adjustment problems with each new wave of immigrants. The newest arrivals are usually given the lowest-paid jobs and are resented by native people who may have to compete with them for those jobs. It has usually taken several decades for each group to be accepted into the mainstream of society in the host country. The purpose of the passage is to discuss______
A. the problems of international migrants
B. the motives of international migrants
C. migration inside the country
D. migration between countries