题目

椭圆的焦点F1 、F2，P为椭圆上的一点，已知，则 的面积为_____________________。 答案：9；  The appeal of advertising to buying motives can have both negative and positive effects. Consumers may be convinced to buy a product of poor quality or high price because of an advertisement. For example, some advertisers have appealed to people’s desire for better fuel economy for their cars by advertising automotive products that improve gasoline mileage. Some of the products work. Others are worthless and a waste of consumers’ money.Sometimes advertising is intentionally misleading. A few years ago a brand ofbread was offered to dieters (节食者) with the message that there were fewer calories in every slice. It turned out that the bread was not dietetic (适合于节食的), but just regular bread. There were fewer calories because it was sliced very thin, but there were the same number of calories in every loaf.　　On the positive side, emotional appeals may respond to a consumer’s real concerns. Consider fire insurance. Fire insurance may be sold by appealing to fear of loss. But fear of loss is the real reason for fire insurance. The security of knowing that property is protected by insurance makes the purchase of fire insurance a worthwhile investment for most people. If consumers consider the quality of the insurance plans as well as the message in the ads, they will benefit from the advertising.　　Each consumer must evaluate her or his own situation. Are the benefits of the product important enough to justify buying it? Advertising is intended to appeal to consumers, but it does not force them to buy the product. Consumers still control the final buying decision.56. Advertising can persuade the consumer to buy worthless products by _________.　 A. stressing their high quality　 B. convincing him of their low price　 C. maintaining a balance between quality and price　 D. appealing to his buying motives57. The reason why the bread advertisement is misleading is that ________.　 A. thin slices of bread could contain more calories　 B. the loaf was cut into regular slices　 C. the bread was not genuine bread　 D. the total number of calories in the loaf remained the same58. The passage tells us that _______.　 A. sometimes advertisements really sell what the consumer needs　 B. advertisements occasionally force consumers into buying things they don’t need　 C. the buying motives of consumers are controlled by advertisements　 D. fire insurance is seldom a worthwhile investment59. It can be inferred from the passage that a smart consumer should ________.　 A. think carefully about the benefits described in the advertisements　 B. guard against the deceiving nature of advertisements　 C. be familiar with various advertising strategies　 D. avoid buying products that have strong emotional appeal60. The passage is mainly about ________.　 A. how to make a wise buying decision　 B. ways to protect the interests of the consumer　 C. the positive and negative aspects of advertising　 D. the function of advertisements in promoting sales