逻辑小班加强削弱bf笔记版

1、 Critical ReasoningStrengthen1. Wood smoke contains dangerous toxins that cause changes in human cells. Because wood smoke presents such a high health risk, legislation is needed to regulate the use of open-air fires and wood-burning stoves.Which of the following, if true, provides the most support

2、for the argument above?(A) The amount of dangerous toxins contained in wood smoke is much less than the amount contained in an equal volume of automobile exhaust.(B) Within the jurisdiction covered by the proposed legislation, most heating and cooking is done with oil or natural gas.(C) Smoke produc

3、ed by coal-burning stoves is significantly more toxic than smoke from wood-burning stoves.(D) No significant beneficial effect on air quality would result if open-air fires were banned within the jurisdiction covered by the proposed legislation.(E) In valleys where wood is used as the primary heatin

4、g fuel, the concentration of smoke results in poor air quality.B选项怎么分析？2. One variety of partially biodegradable plastic beverage container is manufactured from small bits of plastic bound together by a degradable bonding agent such as cornstarch. Since only the bonding agent degrades, leaving the s

5、mall bits of plastic, no less plastic refuse per container is produced when such containers are discarded than when comparable no biodegradable containers are discarded.Which of the following, if true, most strengthens the argument above?(A) Both partially biodegradable and no biodegradable plastic

6、beverage containers can be crushed completely flat by refuse compactors.(B) The partially biodegradable plastic beverage containers are made with more plastic than comparable no biodegradable ones in order to compensate for the weakening effect of the bonding agents.(C) Many consumers are ecology-mi

7、nded and prefer to buy a product sold in the partially biodegradable plastic beverage containers rather than in no biodegradable containers, even if the price is higher. (D) The manufacturing process for the partially biodegradable plastic beverage containers results in less plastic waste than the m

8、anufacturing process for no biodegradable plastic beverage containers.(E) Technological problems with recycling currently prevent the reuse as food or beverage containers of the plastic from either type of plastic beverage container.3. Excavation of the ancient city of Kourion on the island of Cypru

9、s revealed a pattern of debris and collapsed buildings typical of towns devastated by earthquakes. Archaeologists have hypothesized that the destruction was due to a major earthquake known to have occurred near the island in A.D. 365.Which of the following, if true, most strongly supports the archae

10、ologists hypothesis?(A) Bronze ceremonial drinking vessels that are often found in graves dating from years preceding and following A.D. 365 were also found in several graves near Kourion.(B) No coins minted after A.D. 365 were found in Kourion, but coins minted before that year were found in abunda

11、nce.(C) Most modern histories of Cyprus mention that an earthquake occurred near the island in A.D. 365.(D) Several small statues carved in styles current in Cyprus in the century between A.D. 300 and A.D. 400 were found in Kourion.(E) Stone inscriptions in a form of the Greek alphabet that was defi

12、nitely used in Cyprus after A.D. 365 were found in Kourion.C选项为什么不对？4. The use of growth-promoting antibiotics in hog farming can weaken their effectiveness in treating humans because such use can spread resistance to those antibiotics among microorganisms. But now the Smee Company, one of the large

13、st pork marketers, may stop buying pork raised on feed containing these antibiotics. Smee has 60 percent of the pork market, and farmers who sell to Smee would certainly stop using antibiotics in order to avoid jeopardizing their sales. So if Smee makes this change, it will probably significantly sl

14、ow the decline in antibiotics effectiveness for humans.Which of the following, if true, would most strengthen the argument above?(A) Other major pork marketers will probably stop buying pork raised on feed containing growth-promoting antibiotics if Smee no longer buys such pork.(B) The decline in ho

15、g growth due to discontinuation of antibiotics can be offset by improved hygiene.(C) Authorities are promoting the use of antibiotics to which microorganisms have not yet developed resistance.(D) A phaseout of use of antibiotics for hogs in one country reduced usage by over 50 percent over five year

16、s.(E) If Smee stops buying pork raised with antibiotics, the firms costs will probably increase.D选项为什么不对？5. Studies in restaurants show that the tips left by customers who pay their bill in cash tend to be larger when the bill is presented on a tray that bears a credit-card logo. Consumer psychologi

17、sts hypothesize that simply seeing a credit-card logo makes many credit-card holders willing to spend more because it reminds them that their spending power exceeds the cash they have immediately available.Which of the following, if true, most strongly supports the psychologists interpretation of th

18、e studies?A. The effect noted in the studies is not limited to patrons who have credit cards.B. Patrons who are under financial pressure from their credit-card obligations tend to tip less when presented with a restaurant bill on a tray with a credit-card logo than when the tray has no logo.C. In vi

19、rtually all of the cases in the studies, the patrons who paid bills in cash did not possess credit cards.D. In general, restaurant patrons who pay their bills in cash leave larger tips than do those who pay by credit card.E. The percentage of restaurant bills paid with a given brand of credit card i

20、ncreases when that credit cards logo is displayed on the tray with which the bill is presented. ACD选项怎么考虑？7. A study followed a group of teenagers who had never smoked and tracked whether they took up smoking and how their mental health changed. After one year, the incidence of depression among thos

21、e who had taken up smoking was four times as high as it was among those who had not. Since nicotine in cigarettes changes brain chemistry, perhaps thereby affecting mood, it is likely that smoking contributes to depression in teenagers.Which of the following, if true, most strengthens the argument?(

22、A) Participants who were depressed at the start of the study were no more likely to be smokers after one year than those who were not depressed.(B) The study did not distinguish between participants who smoked only occasionally and those who were heavy smokers.(C) Few, if any, of the participants in

23、 the study were friends or relatives of other participants.(D) Some participants entered and emerged from a period of depression within the year of the study.(E) The researchers did not track use of alcohol by the teenagers.Weaken1. Tiger sharks are common in the waters surrounding Tenare Island. Us

24、ually tiger sharks feed on smaller sharks, but sometimes they have attacked tourists swimming and surfing at Tenares beaches. This has hurt Tenares tourism industry, which is second only to its fishing industry in annual revenues. In order to help the economy, therefore, the mayor of the island has

25、proposed an ongoing program to kill any tiger sharks within a mile of the beaches.Which of the following, if true, most strongly calls into question the likelihood that implementation of the mayors proposal will have the desired consequence?(A) Even if not all the tiger sharks that come close to the

26、 beaches are killed, the existence of the program would reassure tourists.(B) Business owners who depend on tourism are willing to pay most of the cost of implementing the program.(C) Tourists come to Tenare Island for its beaches, even though the island features a number of other tourist attraction

27、s.(D) The small sharks on which tiger sharks prey feed on fish that are commercially important to the islands fisheries.(E) Not all tourists who come to Tenare Island enjoy swimming or surfing.AC选项有什么区别？2. To prevent a newly built dam on the Chiff River from blocking the route of fish migrating to b

28、reeding grounds upstream, the dam includes a fish pass, a mechanism designed to allow fish through the dam. Before the construction of the dam and fish pass, several thousand fish a day swam upriver during spawning season. But in the first season after the projects completion, only 300 per day made

29、the journey. Clearly, the fish pass is defective.Which of the following, if true, most seriously weakens the argument?(A) Fish that have migrated to the upstream breeding grounds do not return down the Chiff River again.(B) On other rivers in the region, the construction of dams with fish passes has

30、 led to only small decreases in the number of fish migrating upstream.(C) The construction of the dam stirred up potentially toxic river sediments that were carried downstream.(D) Populations of migratory fish in the Chiff River have been declining slightly over the last 20 years.(E) During spawning

31、 season, the dam releases sufficient water for migratory fish below the dam to swim upstream.ADE选项怎么分析？3. Unlike the wholesale price of raw wool, the wholesale price of raw cotton has fallen considerably in the last year. Thus, although the retail price of cotton clothing at retail clothing stores h

32、as not yet fallen, it will inevitably fall.Which of the following, if true, most seriously weakens the argument above?(A) The cost of processing raw cotton for cloth has increased during the last year.(B) The wholesale price of raw wool is typically higher than that of the same volume of raw cotton.

33、(C) The operating costs of the average retail clothing store have remained constant during the last year.(D) Changes in retail prices always lag behind changes in wholesale prices.(E) The cost of harvesting raw cotton has increased in the last year.E选项为什么不对？4. In the nation of Partoria, large trucks

34、 currently account for 6 percent of miles driven on Partorias roads but are involved in 12 percent of all highway fatalities. The very largest trucksthose with three trailershad less than a third of the accident rate of single- and double-trailer trucks. Clearly, therefore, one way for Partoria to r

35、educe highway deaths would be to require shippers to increase their use of triple-trailer trucks.Which of the following, if true, most seriously weakens the argument?(A) No matter what changes Partoria makes in the regulation of trucking, it will have to keep some smaller roads off-limits to all lar

36、ge trucks.(B) So far only the best, most experienced drivers for Partorian trucking companies have been driving triple-trailer trucks.(C) Very few fatal collisions involving trucks in Partoria are collisions between two trucks.(D) In Partoria, the safety record of the trucking industry as a whole ha

37、s improved slightly over the past ten years.(E) In Partoria, the maximum legal payload of a triple-trailer truck is less than three times the maximum legal payload of the largest of the single-trailer trucks.5.Start-up companies financed by venture capitalists have a much lower failure rate than com

38、panies financed by other means. Source of financing, therefore, must be a more important causative factor in the success of a start-up company than are such factors as the personal characteristics of the entrepreneur, the quality of strategic planning, or the management structure of the company.Whic

39、h of the following, if true, most seriously weakens the argument above?(A) Venture capitalists tend to be more responsive than other sources of financing to changes in a start-up companys financial needs.(B) The strategic planning of a start-up company is a less important factor in the long-term suc

40、cess of the company than are the personal characteristics of the entrepreneur.(C) More than half of all new companies fail within five years.(D) The management structures of start-up companies are generally less formal than the management structures of ongoing businesses.(E) Venture capitalists base

41、 their decisions to fund start-up companies on such factors as the characteristics of the entrepreneur and quality of strategic planning of the company.AB选项为什么不对？6. Since the mayors publicity campaign for Greenvilles bus service began six months ago, morning automobile traffic into the midtown area

42、of the city has decreased 7 percent. During the same period, there has been an equivalent rise in the number of persons riding buses into the midtown area. Obviously, the mayors publicity campaign has convinced many people to leave their cars at home and ride the bus to work.Which of the following,

43、if true, casts the most serious doubt on the conclusion drawn above?(A) Fares for all bus routes in Greenville have risen an average of 5 percent during the past six months.(B) The mayor of Greenville rides the bus to City Hall in the citys midtown area.(C) Road reconstruction has greatly reduced th

44、e number of lanes available to commuters in major streets leading to the midtown area during the past six months.(D) The number of buses entering the midtown area of Greenville during the morning hours is exactly the same now as it was one year ago.(E) Surveys show that longtime bus riders are no mo

45、re satisfied with the Greenville bus service than they were before the mayors publicity campaign began.DE选项为什么不对？Bold Face1. Public health expert: Increasing the urgency of a public health message may be counterproductive. In addition to irritating the majority who already behave responsibly, it may

46、 undermine all government pronouncements on health by convincing people that such messages are overly cautious. And there is no reason to believe that those who ignore measured voices will listen to shouting. The two sections in boldface play which of the following roles in the public health experts

47、 argument?(A) The first is a conclusion for which support is provided, but is not the arguments main conclusion; the second is an unsupported premise supporting the arguments main conclusion.(B) The first is a premise supporting the only explicit conclusion; so is the second.(C) The first is the arg

48、uments main conclusion; the second supports that conclusion and is itself a conclusion for which support is provided.(D) The first is a premise supporting the arguments only conclusion; the second is that conclusion.(E) The first is the arguments only explicit conclusion; the second is a premise suppo