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[案例描述] 西北地区某学生食堂在给学生提供的套餐中有二米粥、烧牛肉、玉米面窝头、蔬菜等，合理的搭配大大提高了学生膳食的营养质量。 这个原理遵循的原则是______。
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After a shaky start, the Martian flotilla that has arrived over the past few weeks is getting down to business. Two of the five craft in it seem to be working perfectly. Two are lost, And a fifth is sick, but undergoing treatment. The most spectacular pictures so far have been provided by Mars Empress, the European Space Agency’s contribution to the fleet. On January 28th this reached its final working orbit (which takes it over both poles, and thus allows it to see the whole of Mars over the course of a few days as the planet revolves beneath it). It has, however, been sending back data since shortly after it arrived, and a few days ago its controllers released a series of beautiful photographs, including a stereo image of Valles Marineris, a huge canyon that may have been formed by flowing water. The most scientifically significant result, though, has come from Opportunity, America’s second Mars rover. One of Opportunity’s cameras has photographed evidence of stratification. in nearby rocks. Such stratification indicates that the rocks concerned are sedimentary. The layers could be repeated wind-blown deposits, or consist of ash from successive volcanic eruptions. But the terrestrial rocks they most resemble are ones that have formed under water. The reason everyone is getting so excited is Because there is a widespread assumption that any form of tire which might dwell on Mars would need liquid water to live--or, even if it could now subsist by extracting moisture from ice, would have needed liquid water to evolve to that stage. Mars has seen more probes launched towards it than all of the other planets put together precisely because of this hope that it might harbour life. So there is a lot riding on the answer--not least the funding of future missions. Besides its scientific significance, the success of Opportunity has also helped to distract attention from the sudden refusal of Spirit, the first American rover to arrive on Mars, to talk to its controllers. This craft had tentatively, but successfully, nosed its way off its landing platform, and was about to drill its way into a nearby rock prior to doing a spot of chemical analysis, when it went silent. However, the engineers at NASA, America’s space agency, are nothing if not resourceful, and they have a good record of carrying out running repairs on spacecraft that are millions of kilometres away. In the case of Spirit, they think that one of the craft’s memory chips has got cluttered up with files created On the journey to Mars. That caused another chip, which manages the first, to throw a wobbly and to keep rebooting the computer. They are currently testing this idea by loading a diagnostic program on to the computer. In addition, as a precaution, they have deleted excess files from the equivalent memory chip on Opportunity. Spirit’s spirits may thus revive. As to the failures, the Japanese abandoned their fly-by craft Nozomi in December, and the British team in charge of Beagle 2, which is presumed to have landed on December 25th but from which no signal has been received, also seems to have called it quits. Still, a 40～60% success rate (depending on whether Spirit is brought back into commission) is not bad by the historical standards of missions to Mars. Now, the real science begins. What does the word "they" (Par
Access中VBA通过数据库引擎可以访问的数据库有以下3种类型：本地数据库；外部数据库和 【9】 。
2006年除夕，李某在其大舅蔡某家门口放鞭炮时，其舅妈郑某因担心鞭炮质量不合格炸伤路 人，不让李某在此燃放。李某认为大舅夫妇刁难他，遂心生不满。几日后，李某酒后大醉，再次来到其大舅家中，因此前之事持折叠刀对蔡某进行威胁。在场的李某的女朋友肖某等人上前对其进行劝阻。劝阻中，李某持刀将肖某扎伤。后肖某因被刺器刺伤左大腿上段，刺破左股动脉、静脉致急性失血性休克死亡。下列说法正确的是( )。
In October 2002, Goldman Sachs and Deutsche Bank (1) a new electronic market (www. gs. com/econderivs) for economic indices that (2) substantial economic risks, such as nonfarm payroll (a measure of job availability) and retail sales. This new market was made possible by a (3) trading technology, developed by Longitude, a New York company providing software for financial markets, (4) the Parimutuel Digital Call Auction. This is "digital" (5) of a digital option: ie, it pays out only if an underlying index lies in a narrow, discrete range. In effect, Longitude has created a horse race, where each "horse" wins if and (6) the specified index falls in a specified range. By creating horses for every possible (7) of the index, and allowing people to bet (8) any number of runners, the company has produced a liquid integrated electronic market for a wide array of options on economic indices.Ten years ago it was (9) impossible to make use of electronic information about home values. Now, mortgage lenders have online automated valuation models that allow them to estimate values and to (10) the risk in their portfolios. This has led to a proliferation of types of home loan, some of (11) have improved risk-management characteristics.We are also beginning to see new kinds of (12) for homes, which will make it possible to protect the value of (13) , for most people, is the single most important (14) of their wealth. The Yale University-Neighbourhood Reinvestment Corporation programme, (15) last year in the city of Syracuse, in New York State, may be a model for home-equity insurance policies that (16) sophisticated economic indices of house prices to define the (17) of the policy. Electronic futures markets that are based on econometric indices of house prices by city, already begun by City Index and IG Index in Britain and now (18) developed in the United States, will enable home-equity insurers to hedge the risks that they acquire by writing these policies.These examples are not impressive successes yet. But they (19) as early precursors of a technology that should one day help us to deal with the massive risks of inequality that (20) will beset us in coming years. Read the following text. Choose the best word (s) for each numbered blank and mark A, B, C or D on Answer Sheet 1.2（）
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