16. The axis of Earth’s daily rotation is tilted with respect to the plane of its orbit at an angle of roughly 23 degrees. That angle can be kept fairly stable only by the gravitational influence of Earth’s large, nearby Moon. Without such a stable and moderate axis tilt, a planet’s climate is too extreme and unstable to support life. Mars, for example, has only very small moons, tilts at wildly fluctuating angles, and cannot support life.
If the statements above are true, which one of the following must also be true on the basis of them?
A. If Mars had a sufficiently large nearby moon, Mars would be able to support life.
B. If Earth’s Moon were to leave Earth’s orbit, Earth’s climate would be unable to support life.
C. Any planet with a stable, moderate axis tilt can support life.
D. Gravitational influences other than moons have little or no effect on the magnitude of the tilt angle of either Earth’s or Mars’s axis.
E. No planet that has more than one moon can support life.
A only by B。 B是A的必要条件, 非B推出非A。
If Earth’s Moon were to leave Earth’s orbit -----〉That angle cannot be kept fairly stable ---
a planet’s climate is too extreme and unstable to support life.( based on Without such a stable and moderate axis tilt, a planet’s climate is too extreme and unstable to support life.)
(B) If Earth’s Moon were to leave Earth’s orbit, Earth’s climate would be unable to support life.
17. Psychologist: Some astrologers claim that our horoscopes completely determine our personalities, but this claim is false, I concede that identical twins---who are, of course, born at practically the same time---often do have similar personalities. However, birth records were examined to find two individuals who were born 40 years ago on the same day and at exactly the same time---one in a hospital in Toronto and one in a hospital in New York. Personalities of these two individuals are in fact different.
Which one of the following is an assumption on which the psychologist’s argument depends?
A. Astrologers have not subjected their claims to rigorous experimentation.
B. The personality differences between the two individuals cannot be explained by the cultural difference between Toronto and New York.
C. The geographical difference between Toronto and New York did not result in the two individuals having different horoscopes.
D. Complete birth records for the past 40 years were kept at both hospitals.
E. Identical twins have identical genetic structures and usually have similar home environments.
18. Modern navigation systems, which are found in most of today’s commercial aircraft, are made with low-power circuitry, which is more susceptible to interference than the vacuum-tube circuitry found in older planes. During landing, navigation systems receive radio signals from the airport to guide the plane to the runway. Recently, one plane with low-power circuitry veered off course during landing, its dials dimming, when a passenger turned on a laptop computer. Clearly, modern aircraft navigation systems are being put at risk by the electronic devices that passengers carry on board, such as cassette players and laptop computers.
Which one of the following, if true, LEAST strengthens the argument above?
A. After the laptop computer was turned off, the plane regained course and its navigation instruments and dials returned to normal.
B. When in use all electronic devices emit electromagnetic radiation, which is known to interfere with circuitry.
C. No problems with navigational equipment or instrument dials have been reported on flights with no passenger-owned electronic devices on board.
D. Significant electromagnetic radiation from portable electronic devices can travel up to eight meters, and some passenger seats on modern aircraft are located within four meters of the navigation systems.
E. Planes were first equipped with low-power circuitry at about the same time portable electronic devices became popular.
19. Jane: Television programs and movies that depict violence among teenagers are extremely popular. Given how influential these media are, we have good reason to believe that these depictions cause young people to engage in violent behavior. Hence, depictions of violence among teenagers should be prohibited from movies and television programs, if only in those programs and movies promoted to young audiences.
Maurice: But you are recommending nothing short of censorship! Besides which, your claim that television and movie depictions of violence cause violence is mistaken: violence among young people predates movies and television by centuries.
Which one of the following, if true, most strengthens Jane’s argument?
A. The most violent characters depicted in movies and on television programs are adult characters who are portrayed by adult actors.
B. The movies that have been shown to have the most influence on young people’s behavior are those that are promoted to young audiences.
C. The people who make the most profits in the movie and television industry are those who can successfully promote their work to both young and old audiences.
D. Many adolescents who engage in violent behavior had already displayed such behavior before they were exposed violence in movies.
E. Among the producers who make both movies and television programs, many voluntarily restrict the subject matter of films directed toward young audiences.
20. A rise in the percentage of all 18-year-olds who were recruited by the armed services of a small republic between 1980 and 1986 correlates with a rise in the percentage of young people who dropped out of high school in that republic. Since 18-year-olds in the republic are generally either high school graduates or high school dropouts, the correlation leads to the conclusion that the republic’s recruitment rates for 18-year-olds depend substantially on recruitment rates for high school dropouts.
Which one of the following statements, if true, most weakens the argument?
A. A large number of 18-year-old high school graduates were recruited for the republic’s armed services in 1986 than in 1980.
B. Many of the high-technology systems used by the republic’s armed services can be operated only by individuals who have completed a high school education.
C. Between 1980 and 1986 the percentage of high school graduates among 18-year-olds recruited in the republic rose sharply.
D. Personnel of the republic’s armed services are strongly encouraged to finish their high school education.
E. The proportion of recruits who had completed at least two years of college education was greater in 1986 than in 1980.
思路：题目的核心是要否定percentage of dropouts 与 percentage of recruitment的因果关系
B：无关选项，和题目的核心比率没有太大关系。Tips: 注意many... only by.....这种表述。
D：无关选项。此类错误属于false appeal。tips:注意.....(机构或人)strongly encourage something
E：无关选项，percentage of those completed college education和题目的核心比率没有太大关系。