Critical Reasoning

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 has not yet fallen, it will inevitably fall. Which of the following, if true, most seriously weakens the argument above?

When three Everett-owned Lightning-built airplanes crashed in the same month, the Everett company ordered three new Lightning-built airplanes as replacements. This decision surprised many in the airline industry because, ordinarily when a product is involved in accidents, users become reluctant to buy that product. Which of the following, if true, provides the best indication that the Everett company�s decision was logically well supported?

Half of the subjects in an experiment�the experimental group�consumed large quantities of a popular artificial sweetener. Afterward, this group showed lower cognitive abilities than did the other half of the subjects�the control group�who did not consume the sweetener. The detrimental effects were attributed to an amino acid that is one of the sweetener�s principal constituents. Which of the following, if true, would best help explain how the sweetener might produce the observed effect?

If there is an oil-supply disruption resulting in higher international oil prices, domestic oil prices in open-market countries such as the United States will rise as well, whether such countries import all or none of their oil Which of the following conclusions is best supported by the statement above?

A certain mayor has proposed a fee of five dollars per day on private vehicles entering the city, claiming that the fee will alleviate the city's traffic congestion. The mayor reasons that, since the fee will exceed the cost of round-trip bus fare from many nearby points, many people will switch from using their cars to using the bus. B The cost of parking fees already makes it considerable more expensive for most people to take a private vehicle into the city than to take a bus. C Most of the people currently riding the bus do not own private vehicles. D Many commuters opposing the mayor's plan have indicated that they would rather endure traffic congestion than pay a five dollar per day fee. E During the average workday, private vehicles owned and operated by people living within the city account for twenty percent of the city's traffic congestion.

In the past most airline companies minimized aircraft weight to minimize fuel costs. The safest airline seats were heavy, and airlines equipped their planes with few of these seats. This year the seat that has sold best to airlines has been the safest one - a clear indication that airlines are assigning a higher priority to safe seating than to minimizing fuel costs. Which of the following, if true, most seriously weakens the argument above?

Certain messenger molecules fight damage to the lungs from noxious air by telling the muscle cells encircling the lungs� airways to contract. This partially seals off the lungs. An asthma attack occurs when the messenger molecules are activated unnecessarily, in response to harmless things like pollen or household dust. Which of the following, if true, points to the most serious flaw of a plan to develop a medication that would prevent asthma attacks by blocking receipt of any messages sent by the messenger molecules referred to above?

Traditionally, decision-making by managers that is reasoned step-by-step has been considered preferable to intuitive decision-making. However, a recent study found that top managers used intuition significantly more than did most middle- or lower-level managers. This confirms the alternative view that intuition is actually more effective than careful, methodical reasoning. The conclusion above is based on which of the following assumptions?

Useful protein drugs, such as insulin, must still be administered by the cumbersome procedure of injection under the skin. If proteins are taken orally, they are digested and cannot reach their target cells. Certain nonprotein drugs, however, contain chemical bonds that are not broken down by the digestive system. They can, thus, be taken orally. The statements above most strongly support a claim that a research procedure that successfully accomplishes which of the following would be beneficial to users of protein drugs?

A report on acid rain concluded, �Most forests in Canada are not being damaged by acid rain.� Critics of the report insist the conclusion be changed to, �Most forests in Canada do not show visible symptoms of damage by acid rain, such as abnormal loss of leaves, slower rates of growth, or higher mortality.� B Acid rain could be causing damage for which symptoms have not yet become visible. C The report does not compare acid rain damage to Canadian forests with acid rain damage to forests in other countries. D All forests in Canada have received acid rain during the past fifteen years. E The severity of damage by acid rain differs from forest to forest.

A program instituted in a particular state allows parents to prepay their children�s future college tuition at current rates. The program then pays the tuition annually for the child at any of the state�s public colleges in which the child enrolls. Parents should participate in the program as a means of decreasing the cost for their children�s college education. B The amount of money accumulated by putting the prepayment funds in an interest-bearing account today will be greater than the total cost of tuition for any of the public colleges when the child enrolls. C The annual cost of tuition at the state�s pubic colleges is expected to increase at a faster rate than the annual increase in the cost of living. D Some of the state�s public colleges are contemplating large increases in tuition next year. E The prepayment plan would not cover the cost of room and board at any of the state�s public colleges.

A museum has been offered an undocumented statue, supposedly Greek and from sixth century B.C. Possibly the statue is genuine but undocumented because it was recently unearthed or because it has been privately owned. However, an ancient surface usually has uneven weathering, whereas the surface of this statue has the uniform quality characteristically produced by a chemical bath used by forgers to imitate a weathered surface. Therefore, the statue is probably a forgery. B The subject�s pose and other aspects of the subject�s treatment exhibit all the most common features of Greek statues of the sixth century B.C. C The chemical bath that forgers use was at one time used by dealers and collectors to remove the splotchy surface appearance of genuinely ancient sculptures. D Museum officials believe that forgers have no technique that can convincingly simulate the patchy weathering characteristic of the surfaces of ancient sculptures. E An allegedly Roman sculpture with a uniform surface similar to that of the statue being offered to the museum was recently shown to be a forgery.

Start-up companies financed by venture capitalist have a much lower failure rate than companies 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. Which of the following, if true, most seriously weakens the argument above?

An eyeglass manufacturer tried to boost sales for the summer quarter by offering its distributors a special discount if their orders for that quarter exceeded those for last year's summer quarter by at least 20 percent. Many distributors qualified for this discount. Even with much merchandise discounted, sales increased enough to produce a healthy gain in net profits. The manufacturer plans to repeat this success by offering the same sort of discount for the fall quarter. Which of the following, if true, most clearly points to a flaw in the manufacturer's plan to repeat the successful performance of the summer quarter?

Half of the subjects in an experiment�the experimental group�consumed large quantities of a popular artificial sweetener. Afterward, this group showed lower cognitive abilities than did the other half of the subjects�the control group�who did not consume the sweetener. The detrimental effects were attributed to an amino acid that is one of the sweetener's principal constituents. Which of the following, if true, would best support the conclusion that some ingredient of the sweetener was responsible for the experimental results?

Some communities in Florida are populated almost exclusively by retired people and contain few, if any, families with small children. Yet these communities are home to thriving businesses specializing in the rental of furniture for infants and small children. Which of the following, if true, best reconciles the seeming discrepancy described above?

It is true that it is against international law to sell plutonium to countries that do not yet have nuclear weapons. But if United States companies do not do so, companies in other countries will. Which of the following is most like the argument above in its logical structure?

A milepost on the towpath read "21" on the side facing the hiker as she approached it and "23" on its back. She reasoned that the next milepost forward on the path would indicate that she was halfway between one end of the path and the other. However, the milepost one mile further on read "20" facing her and "24" behind. B The numbers on the mileposts indicate kilometers, not miles. C The facing numbers indicate miles to the end of the path, not miles from the beginning. D A milepost was missing between the two the hiker encountered. E The mileposts had originally been put in place for the use of mountain bikers, not for hikers.

Airline: Newly developed collision-avoidance systems, although not fully tested to discover potential malfunctions, must be installed immediately in passenger planes. Their mechanical warnings enable pilots to avoid crashes. Pilots: Pilots will not fly in planes with collision-avoidance systems that are not fully tested. Malfunctioning systems could mislead pilots, causing crashes. The pilots� objection is most strengthened if which of the following is true?

Hardin argued that grazing land held in common (that is, open to any user) would always be used less carefully than private grazing land. Each rancher would be tempted to overuse common land because the benefits would accrue to the individuals, while the costs of reduced land quality that results from overuse would be spread among all users. But a study comparing 217 million acres of common grazing land with 433 million acres of private grazing land showed that the common land was in better condition. The answer to which of the following questions would be most useful in evaluating the significance, in relation to Hardin's claim, of the study described above?