Nuclear fusion is a process whereby the nuclei of atoms are joined, or "fused", and in which energy is released. One of the by-products of fusion is helium-4 gas. A recent fusion experiment was conducted using "heavy" water contained in a sealed flask. The flask was, in turn, contained in an air-filled chamber designed to eliminate extraneous vibration. After the experiment, a measurable amount of helium-4 gas was found in the air of the chamber. The experiments cited this evidence in support of their conclusion that fusion had been achieved.
Which one of the following, if true, would cast doubt on the experimenters' conclusion?
(A) Helium-4 was not the only gas founding the experiment chamber.
(B) When fusion is achieved, it normally produces several by-products, including tritium and gamma rays.
(C) The amount of helium-4 found in the chamber's air did not exceed the amount of helium-4 that is found in ordinary air.
(D) Helium-4 gas rapidly breaks down, FORMing ordinary helium gas after a few hours.
(E) Nuclear fusion reactions are characterized by the release of large amount of heat.
Every photograph, because it involves the light rays that something emits hitting film, must in some obvious sense be true. But because it could always have been made to show things differently than it does, it cannot express the whole truth and, in that sense, is false. Therefore, nothing can ever be definitively proved with a photograph.
Which one of the following, if true, would cast doubt on the experimenters' conclusion?
(A) Helium-4 was not the only gas found in the experiment chamber.
(B) When fusion is achieved, it normally produces several by-products, including tritium and gamma rays.
(C) The amount of helium-4 found in the chamber's air did not exceed the amount of helium-4 that is found in ordinary air.
(D) Helium-4 gas rapidly breaks down, FORMing ordinary helium gas after a few hours.
(E) Nuclear fusion reactions are characterized by the release of large amount of heat.
Some cleaning fluids, synthetic carpets, wall paneling, and other products release toxins, such as FORMaldehyde and benzene, into the household air supply. This is not a problem in well-ventilated houses, but it is a problem in houses that are so well insulated that they trap toxins as well as heat. Recent tests, however, demonstrate that houseplants remove some household toxins from the air and thereby eliminate their danger. In one test, 20 large plants eliminated FORMaldehyde from a small, well-insulated house.
Assume that a person who lives in a small, well-insulated house that contains toxin-releasing products places houseplants, such as those tested, in the house.
Which one of the following can be expected as a result?
(A) There will no longer be any need to ventilate the house.
(B) The concentration of toxins in the household air supply will remain the same.
(C) The house will be warm and have a sage air supply.
(D) If there is FORMaldehyde in the household air supply, its level will decrease.
(E) If FORMaldehyde benzene are being released of each will decrease.
The passage is structured to lead to which one of the following conclusions?
(A) Houseplants can remove benzene from the air.
(B) Nonsynthetic products do not release toxins into houses.
(C) Keeping houseplants is an effective means of trapping heat in a poorly insulated house.
(D) Keeping houseplants can compensate for some of the negative effects of poor ventilation.
(E) The air in a well-insulated house with houseplants will contain fewer toxins than the air in a well-ventilated house without houseplants.
In opposing the 1970 Clean Air Act, the United States automobile industry argued that meeting the act's standards for automobile emissions was neither economically feasible nor environmentally necessary. However, the catalytic converter, invented in 1967, enabled automakers to meet the 1970 standards efficiently. Currently, automakers are lobbying against the government's attempt to pass legislation that would tighten restrictions on automobile emissions. The automakers contend that these new restrictions would be overly expensive and unnecessary to efforts to curb air pollution. Clearly, the automobile industry's position should not be heeded.
Which one of the following most accurately expresses the method used to counter the automakers' current position?
(A) The automakers' premises are shown to lead to a contradiction.
(B) Facts are mentioned that show that the automakers are relying on false inFORMation.
(C) A flaw is pointed out in the reasoning used by the automakers to reach their conclusion.
(D) A comparison is drawn between the automakers' current position and a position they held in the past.
(E) Evidence is provided that the new emissions legislation is both economically feasible and environmentally necessary.
Which one of the following, if true, lends the most support to the automakers' current position?
(A) The more stringent the legislation restricting emission becomes, the more difficult it becomes for automakers to provide the required technology economically.
(B) Emissions-restriction technology can often be engineered so as to avoid reducing the efficiency with which an automobile uses fuel.
(C) Not every new piece of legislation restricting emission requires new automotive technology in order for automakers to comply with it.
(D) The more automobiles there are on the road, the more stringent emission restrictions must be to prevent increased overall air pollution.
(E) Unless forced to do so by the government, automakers rarely make changes in automotive technology that is not related to profitability.
A survey was recently conducted among ferry passengers on the North Sea. Among the results was this: more of those who had taken anti-seasickness medication before their trip reported symptoms of seasickness than those who had not taken such medication. It is clear, then, that despite claims by drug companies that clinical tests show the contrary, people would be better off not taking anti-seasickness medications.
Which one of the following, if true, would most weaken the conclusion above?
(A) Given rough enough weather, most ferry passengers will have some symptoms of seasickness.
(B) The clinical tests reported by the drug companies were conducted by the drug companies' staffs.
(C) People who do not take anti-seasickness medication are just as likely to respond to a survey on seasickness as people who do.
(D) The seasickness symptoms of the people who took anti-seasickness medication would have been more severe had they not taken the medication.
(E) People who have spent money on anti-seasickness medication are less likely to admit symptoms of seasickness than those who have not.
Court records from medieval France show that in the years 1300 to 1400 the number of people arrested in the French realm for "violent interpersonal crimes" (not committed in wars) increased by 30 percent over the number of people arrested for such crimes in the years 1200 to 1300. If the increase was not the result of false arrests, therefore, medieval France had a higher level of documented interpersonal violence in the years 1300 to 1400 than in the years 1200 to 1300.
Which one of the following statements, if true, most seriously weakens the argument?
(A) In the years 1300 to 1400 the French government's category of violent crimes included an increasing variety of interpersonal crimes that are actually nonviolent.
(B) Historical accounts by monastic chroniclers in the years 1300 to 1400 are filled with deions of violent attacks committed by people living in the French realm.
(C) The number of individual agreements between two people in which they swore oaths not to attack each other increased substantially after 1300.
(D) When English armies tried to conquer parts of France in the mid-to late 1300s, violence in the northern province of Normandy and the southwestern province of Gascony increased.
(E) The population of medieval France increased substantially during the first five decades of the 1300s, until the deadly bubonic plague decimated the population of France after 1348.
Rhizobium bacteria living in the roots of bean plants or other legumes produce fixed nitrogen, which is one of the essential plant nutrients and which for non-legume crops, such as wheat, normally must be supplied by applications of nitrogen-based fertilizer. So if biotechnology succeeds in producing wheat strains whose roots will play host to Rhizobium bacteria, the need for artificial fertilizers will be reduced.
The argument above makes which one of the following assumptions?
(A) Biotechnology should be directed toward producing plants that do not require artificial fertilize.
(B) Fixed nitrogen is currently the only soil nutrient that must be supplied by artificial fertilizer for growing wheat crops.
(C) There are no naturally occurring strains of wheat or other grasses that have Rhizobium bacteria living in their roots.
(D) Legumes are currently the only corps that produce their own supply of fixed nitrogen.
(E) Rhizobium bacteria living in the roots of wheat would produce fixed nitrogen.
Current legislation that requires designated sections for smokers and nonsmokers on the premises of privately owned businesses is an intrusion into the private sector that cannot be justified. The fact that studies indicate that nonsmokers might be harmed by inhaling the smoke from others' cigarettes is not the main issue. Rather, the main issue concerns the government's violation of the right of private businesses to determine their own policies and rules.
Which of the following is a principle that, if accepted, could enable the conclusion to be properly drawn?
(A) Government intrusion into the policies and rules of private businesses is justified only when individuals might be harmed.
(B) The right of individuals to breathe safe air supersedes the right of businesses to be free from government intrusion.
(C) The right of businesses to self-determination overrides whatever right or duty the government may have to protect the individual.
(D) It is the duty of private businesses to protect employees from harm in the workplace.
(E) Where the rights of businesses and the duty of government conflict, the main issue is finding a successful compromise.
