The teacher gives students 2 minutes to skim a text, andwhen time is up, he asks studentsto stop and answer some questions. Here theteacher is playing the role of a(an) __________ .

单项选择题请阅读短文，完成第题。Results showed that at least a tenth of the Harvard first-yearundergraduates polled admitted tohaving cheated on an exam prior to starting atthe university, while almost half admitted to cheatingon their homework. Ananonymous survey by Harvard's newspaper has revealed a surprisingpattern ofacademic dishonesty among students entering the US universities.The survey by The Harvard Crimson was emailed to the incomingfirst year undergraduates;1,600 students responded. Results showed that atleast a tenth of the students polled admitted tohaving cheated on an exam priorto starting at the university, while almost half admitted to cheatingon theirhomework.Athletes were apparently the most prone to cheating.20 percentof students who played auniversity sport admitted to cheating on an examcompared to 9 percent of students who did not.The survey also revealed that menwere not only more likely to cheat but were also more likely toadmit to it.The results, compared to a previous survey done on the class of2013, suggested that cheatingmay be becoming more commonplace. Of the outgoingseniors only 7 percent admitted to cheatingin an exam and another 7 percentsaid they had been dishonest on a take-home test.32 percent ofthe seniors saidthey had cheated on homework during their undergraduate years.The surveys come in the wake of a cheating scandal at theuniversity which saw 120 studentsinvestigated for sharing answers on an exam in2012. One recent graduate stated: Cheating wascommonplace when I was atHarvard, especially with students in their first year or two. I would sayasmany as 60 percent of students took notes into some exams. No one really caredthe faculty, wellsome of them at least, seemed to recognize and yet ignore theproblem. In an email to NBC News, Jeff Neal, a Harvard representative,explained that a committee,made up of faculty, staff and students had beenestablished to tackle cheating, which is a nationalproblem in Americaneducation .He added: While the vast majority of Harvard and otherstudents do their work honestly,beginning this year Harvard College hasimplemented a new, more robust strategy of communicatingwith all students,particularly first-year students, about the importance--and the ways toachieve--academic integrity. In a rebuff to critics who say university has become littlemore than an expensive party,84 percentoftherespondingundergraduatesfullyexpectedtoprioritizetheiracademicsoverextracurricularactivities, sport, employment and their social lives. Not a single studentputacademics at the bottom of their list. Not content with confining themselvesto their degree subject, 59 percent of incoming students expressed a desire to pursue asecondary field of study, and 36 percent hoped to learn a language.What did the results show according to the first twoparagraphs?

单项选择题请阅读短文，完成第题。Polyester(聚酯 ) is nowbeing used for bottles. ICI, the chemicals and plastics company, believes thatit is now beginning to break the grip of glass on the bottle business and thustake advantage of this huge market.All theplastics manufacturers have been experiencing hard times as their traditionalproducts have been doing badly world-wide for the last few years. Between 1982and 1984 the Plastics Division of ICI had lost a hundred and twenty milliondollars, and they felt that the most hopeful new market was in packaging,bottles and cans.Since1982 it has opened three new factories producing Melinar , the rawmaterial from which high quality polyester bottles are made.Thepolyester bottle was born in the 1970s, when soft drinks companies like CocaCola started selling their drinks in giant two-liter containers. Because of thebuild-up of the pressure of gas in these large containers, glass wasunsuitable. Nor was PVC, the plastic which had been used for bottles since the1960s, suitable for drinks with gas in them. A new plastic had to be made.Glass isstill cheaper for the smaller bottles and will continue to be so, unless oiland plastic become much cheaper, but plastic does well for the larger sizes.Polyesterbottles are virtually unbreakable. The manufacturers claim they are alsolighter, less noisy when being handled, and can be reused. Shopkeepers andother business people are unlikely to object to a change from glass topolyester, since these bottles mean few breakages, which are costly andtime-consuming. The public, though, have been more difficult to persuade. ICI'scommercial department is developing different bottles with interesting shapes,to try and make them visually more attractive to the public.The nextstep could be to develop a plastic which could replace tins for food. Theproblem here is the high temperatures necessary for cooking the food in thecontainer. Whyis ICI's Plastics Division interested in polyester for bottles?