单选题In an animal behavior experiment, 50 tagged white pigeons and 200 tagged gray pigeons were released from a laboratory. Within one week, 88 percent of the white pigeons and 80.5 percent of the gray pigeons had returned to the laboratory. What percent of the total number of pigeons returned to the laboratory? A. 80.5 B. 82 C. 82.5 D. 85 E. 86.5

单选题His parents died when he was young, so he was ____ by his grandma

单选题What is the value of 3x2-1.8x+0.3 for x=0.6? A. -0.3 B. 0 C. 0.3 D. 1.08 E. 2.46

单选题_______，the2007NobelPrizeWinnerforLiterature,isaPersian‐born,Rhodesian(nowZimbabwe)‐raisedBritishnovelistwhodiedin2013.

单选题The following two questions are based on the following passage: A study by a group of dentists has concluded that regular use of a certain brand of mouthwash is as effective as flossing in preventing gum disease. The mouthwash company has released a television ad suggesting that people who do not like flossing can now rely solely on mouthwash and brushing to maintain good dental health. A leading manufacturer of dental floss brought a lawsuit against the mouthwash company demanding that the advertisement be discontinued on the grounds that it is misleading.

单选题The next two questions refer to the following passage: A pharmaceutical company tested a new painkiller on 1,000 lab rats that were fed large doses of the painkiller for a two-month period. By the end of the experiment, 39 of tile rats had died. The company concluded that the painkiller was sufficiently safe to test on humans.

单选题Since the World Wide Web was created in 1990, the only way to get onto the Internet has been through a computer, a costly box that ______ people as much today as the telephone did 50 years ago.

单选题The number of small national and regional electronic-money providers will ______ as the neatest among them, such as Belgium"s Proton and Denmark"s Danmont, get swallowed by international consortia, such as Mondex has been already snapped by MasterCard.

单选题AcoedsoccerteamhasWwomenandMmenontheteam.If4womenand2menareaddedtotheteamroster,andifonepersonontheteamisselectedatrandomtoserveasteamcaptain,thentheprobabilitythattheteamcaptainwillbeawomancanberepresentedas

单选题Every year television stations receive hundreds of complaints about the loudness of advertisements. However, federal rules forbid the practice of making ads louder than the programming. In addition, television stations always operate at the highest sound level allowed for reasons of efficiency. According to one NBC executive, no difference exists in the peak sound level of ads and programming. Given this information why do commercials sound so loud? The sensation of sound involves a variety of factors in addition to its speak level. Advertisers are skilful at creating the impression of loudness through their expert use of such factors. One major contributor to the perceived loudness of commercials is that much less variation in sound level occurs during a commercial. In regular programming the intensity of sound varies over a large range. However, sound levels in commercials tend to stay at or near peak levels. Other "tricks of the trade" are also used. Because low-frequency sounds can mask higher frequency sounds, advertisers filter out any noises that may drown out the primary message. In addition, the human voice has more auditory (听觉的) impact in the middle frequency ranges. Advertisers electronically vary voice sounds so that they stay within such a frequency band. Another approach is to write the script so that lots of consonants are used, because people are more aware of consonants than vowel sounds. Finally, advertisers try to begin commercials with sounds that are highly different from those of the programming within which the commercial is buried. Because people become adapted to the type of sounds coming from programming, a dramatic change in sound quality draws viewer"s attention. For example, notice how many commercials begin with a cheerful song of some type. The attention-getting property of commercials can be seen by observing one-to two-year-old children who happen to be playing around a television set. They may totally ignore the programming. However, when a commercial comes on, their attention is immediately drawn to it because of its dramatic sound quality.

单选题__________youunderstandtherule,youwillhavenofurtherdifficulty.

单选题Recent scientific studies have proven that ulcers are caused, at least in part, by the heliobacter bacterium. Dr. Redding has hypothesized that a natural way to prevent and cure ulcers is to eat large amounts of raw broccoli, which contains potent organic compounds that are beneficial to gastric health. All of the following statements support Dr. Redding's hypothesis, EXCEPT: A. It has been shown that people who consume raw broccoli on a regular basis have a 65 percent lower chance of developing ulcers than do the general population. B. One of the organic compounds found in broccoli has been shown to have an antibiotic effect on the heliobacter bacterium. C. Dr. Redding conducted a study in which groups of patients suffering from ulcers either ate large quantities of broccoli or ate a diet that included no vegetables; several of the patients who ate the large quantities of broccoli showed marked improvement in their conditions. D. Broccoli is one of the most potent dietary sources of antioxidants, the organic compounds shown to combat the free radicals that are thought to cause cancer. E. Test animals with chemically induced ulcers showed some signs of improvement when raw broccoli was incorporated into their diets.

单选题The current emergency in Mexico City that has taken over our lives is nothing. I could ever have imagined for me or my children. We are living in an environmental crisis, an air-pollution emergency of severity. What it really means is that just to breathe here is to play a dangerous game with your health. As parents, what terrorizes us most are reports that children are at higher risk because they breathe more times per minute. What more can we do to protect them and ourselves? Our pediatrician"s (儿科医师的) medical recommendation was simple, abandon the city permanently. We are foreigners and we are among the small minority that can afford to leave. We are here because of my husband"s work. We are fascinated by Mexico—its history and rich culture. We know that for us, this is a temporary danger. However, we cannot stand for much longer the fear we feel for our boys. We cannot stop them from breathing. But for millions, there is no choice. Their lives, their jobs, their futures depend on being here. Thousands of Mexicans arrive each day in this city, desperate for economic opportunities. Thousands more are born here each day. Entire families work in the streets and practically live there. It is a familiar sight, as parents hawk goods at stoplights, their children play in the grassy highway dividers, breathing exhaust fumes. I feel guilty complaining about my personal situation; we won"t be here long enough for our children to form the impression that skies are colored only gray. And yet the government cannot do what it must to end this problem. For any country, especially a developing Third World economy like Mexico"s, the idea of barring from the capital city enough cars, closing enough factories and spending the necessary billions on public transportation is simply not an option. So when things get bad, as in the current emergency, Mexico takes half measures—prohibiting some more cars from circulating, stopping some factories from producing—that even its own officials concede aren"t adequate. The word "emergency" implies the unusual. But when daily life itself is an emergency, the concept loses its meaning. It is human nature to try to adapt to that which we cannot change, or to mislead ourselves into believing we can adapt.

单选题[Focusonstateofvoicing]

单选题The Comfocar company manufactures a sedan that can drive comfortably at 80 miles per hour. A rival company, Turbocar, recently introduced a comparably equipped sedan that can drive comfortably at up to 110 miles per hour. Turbocar claims that its sedan will outsell Comfocar's sedan because the Turbocar sedan can get customers to their destinations in comfort much faster than can the Comfocar sedan. Which of the following, if true, casts the most doubt on Turbocar's claims? A. Customers in surveys consistently rank comfort among the most important criteria in purchasing a car. B. Many road surfaces are engineered to allow comfortable driving at speeds up to 120 miles per hour. C. Automotive safety experts state that it is not safe for any car to be driven faster than 100 miles per hour. D. Comprehensive research has determined that while the Turbocar model has faster acceleration and a higher top speed than the Comfocar sedan, both cars show approximately the same fuel efficiency. E. Nowhere in the main marketing areas for these two car companies is it legal or practical to drive faster than 70 miles per hour.

单选题______ other than compounds may be divided into roots and affixes. A. Polymorphemic words B. Bound morphemes C. Free morphemes

单选题A.0.0008B.0.001C.0.008D.0.04E.0.08

单选题The following data sufficiency problems consist of a question and two statements, labeled (1) and (2), in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the statements plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of counterclockwise), you must indicate whether Ａ. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient. Ｂ. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient. Ｃ. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient. Ｄ. EACH statement ALONE is sufficient. Ｅ. Statements (1) and (2) TOGETHER are NOT sufficient.

单选题Skilled blacksmiths who could forge useful items out of iron used to play a central role in American life. The onset of industrialization and the mass production of iron products, however, have made the blacksmith's traditional role mostly obsolete. Still, there will always be a job available for a good blacksmith. Which of the following, if true, provides the most support for the conclusion that a job will always be available for a good blacksmith? A. Many people are willing to pay considerably more for tools hand-crafted by a blacksmith than for tools created by a machine. B. Blacksmiths cannot produce iron products with the speed or consistency of machines. C. Blacksmiths traditionally apprenticed to a master blacksmith for seven or more years before entering business independently. D. The cowboy never would have conquered the West without the horseshoes crafted by blacksmiths. E. As skilled craftsmen, blacksmiths traditionally served as community leaders throughout North America and Europe.