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[Critical Reasoning]

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题目：

Which of the following most logically completes the passage?
Using new detection techniques, researchers have found trace amounts of various medicinal substances in lakes and rivers. Taken in large quantities, these substances could have serious health effects, but they are present in quantities far too low to cause any physiological response in people who drink the water or bathe in it. Nevertheless, medical experts contend that eliminating these trace amounts from the water will have public health benefits, since_____.

选项:

A、some of the medicinal substances found in lakes and rivers are harmless to humans even if taken in large quantities
B、some of the medicinal substances found in lakes and rivers can counteract possible harmful effects of other such substances found there 
C、people who develop undesirable side effects when being treated with medicines that contain these substances generally have their treatment changed 
D、most medicinal substances that reach lakes or rivers rapidly break down into harmless substances 
E、disease-causing bacteria exposed to low concentrations of certain medicinal substances can become resistant to them

答案:

E
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[Sentence Correction]

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题目：

After increasing steadily for centuries, the total annual catch of all wild fish peaked in 1989; since that time, the total catch for most species has declined or plateaued, prompting conservation efforts designed to help prevent population crashes and possible extinctions.

选项:

A、fish peaked in 1989; since that time, the total catch for most species has declined or plateaued, prompting
B、fish peaked in 1989, but with the total catch since then declining or plateauing in the case of most species, prompting
C、fish had peaked in 1989; since that time, the decline or plateau of the total catch for most species, which prompted
D、fish, which peaked in 1989, and, in the case of most species, it has declined or plateaued since, prompted
E、fish, which peaked in 1989 but has since declined or plateaued for most species, and this prompted

答案:

A
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[Sentence Correction]

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题目：

Britain's economic growth was slower in the mid-1970's and its decline much more rapid in the subsequent recession than the United States.

选项:

A、Britain's economic growth was slower in the mid-1970's and its decline much more rapid in the subsequent recession than the United States.
B、The economic growth of Britain was slower in the mid-1970's and it declined much more rapidly in the subsequent recession than the United States did.
C、Britain's economy, which grew more slowly in the mid-1970's, also had declined much more rapidly in the subsequent recession than the United States did.
D、The economy of Britain grew more slowly in the mid-1970's and declined much more rapidly in the subsequent recession than did the economy of the United States.
E、 Britain's economy grew more slowly in the mid-1970's and its decline was much more rapid during the subsequent recession than the economy of the United States.

答案:

D
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[Sentence Correction]

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题目：

Both the caribou and the reindeer belong to the species Rangifer tarandus, but after 7,000 years of domestication in Eurasia, reindeer have developed a tendency to circle in tight groups, while caribou tend to spread far and wide.

选项:

A、belong to the species Rangifer tarandus, but after 7,000 years of domestication in Eurasia, reindeer have developed a tendency to circle in tight groups, while caribou tend
B、belong to the same species, Rangifer tarandus, but about 7,000 years of domestication in Eurasia have developed reindeer's tendency to circle in tight groups, which is different from caribou that tend
C、belong to the species Rangifer tarandus, but being domesticated in Eurasia for about 7,000 years has developed reindeer's tendency to circle in tight groups, and that is different from caribou tending
D、are the same species, Rangifer tarandus, but about 7,000 years of domestication in Eurasia have developed reindeer's tendency to circle in tight groups, while the tendency is for caribou
E、are the same species, Rangifer tarandus, but being domesticated in Eurasia for about 7,000 years has developed the reindeer's tendency to circle in tight groups, which differs from caribou tending

答案:

A
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[Reading Comprehension]

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文章：

    The dry mountain ranges of the Western united states contain rocks dating back 440 to 510 million years, to the Ordovician period, and teeming with evidence of tropical marine life. This rock record provides clues about one of the most significant radiations (periods when existing life-forms gave rise to variations that would eventually) evolve into entirely new species) in the history of marine invertebrates. During this radiation the number of marine biological families increased greatly, and these families included species that would dominate the marine ecosystems of the area for the next 215 million years. Although the radiation spanned tens of millions of years, major changes in many species occurred during a geologically short time span within the radiation and, furthermore, appear to have occurred worldwide, suggesting that external events were major factors in the radiation. And , in fact, there is evidence of major ecological and geological changes during this period: the sea level dropped drastically and mountain ranges were formed, in this instance, rather than leading to large-scale extinctions, these kinds of environmental changes may have resulted in an enriched pattem of habitats and nutrients, which in turn gave rise to the Ordovician radiation, However, the actual relationship between these environmental factors and the diversification of life forms is not yet fully understood.

题目：

Which of the following can be inferred from the passage regarding the geologic changes that occurred during Ordovician period?

选项:

A、They were more drastic than those associated with other radiations
B、They may have created conditions favorable to the evolution of many new life-forms
C、They may have caused the extinction of many of the marine species living in shallow waters
D、They may have been a factor in the development of new species adapted to living both on land and in water .
E、They hastened the formation of the extensive dry regions found in the western united states

答案:

B
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[Problem Solving]

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题目：

A certain experimental mathematics program was tried out in 2 classes in each of 32 elementary schools and involved 37 teachers. Each of the classes had 1 teacher and each of the teachers taught at least 1, but not more than 3, of the classes. If the number of teachers who taught 3 classes is n, then the least and greatest possible values of n, respectively, are

选项:

A、0 and 13
B、0 and 14
C、1 and 10
D、1 and 9
E、2 and 8

答案:

A
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[Reading Comprehension]

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文章：

Line         Io and Europa, the inner two of Jupiter’s four
  largest moons, are about the size of Earth’s moon
  and are composed mostly or entirely of rock and
  metal. Ganymede and Callisto are larger and roughly
(5) half ice. Thus, these four moons are somewhat
  analogous to the planets of the solar system, in which
  the rock- and metal-rich inner planets are distinct
  from the much larger gas- and ice-rich outer planets.
  Jupiter’s moons are, however, more “systematic”:
(10) many of their properties vary continuously with
  distance from Jupiter. For example, Io is ice-free,
  Europa has a surface shell of ice, and while
  Ganymede and Callisto are both ice-rich, outermost
  Callisto has more.
(15)      This compositional gradient has geological
  parallels. Io is extremely geologically active, Europa
  seems to be active on a more modest scale, and
  Ganymede has undergone bouts of activity in its
  geological past. Only Callisto reveals no geological
(20) activity. In similar fashion, Callisto’s surface is very
  heavily cratered from the impact of comets and
  asteroids; Ganymede, like Earth’s moon, is heavily
  cratered in parts; Europa is very lightly cratered; and
  no craters have been detected on Io, even though
(25) Jupiter’s gravity attracts comets and asteroids
  passing near it, substantially increasing the
  bombardment rate of the inner moons compared
  to that of the outer ones. But because of Io’s high
  degree of geological activity, its surface undergoes
(30) more-or-less continuous volcanic resurfacing.


题目：

According to the passage, the difference in the amount of cratering on Callisto’s and Io’s respective surfaces can probably be explained by the difference between these two moons with respect to which of the following factors?

选项:

A、Size
B、Ice content
C、The rate of bombardment by comets and asteroids
D、The influence of Jupiter’s other moons
E、The level of geological activity

答案:

E
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[Sentence Correction]

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题目：

Simply because they are genetically engineered does not make it any more likely for plants to become an invasive or persistent weed, according to a decade-long study published in the journal Nature.

选项:

A、 because they are genetically engineered does not make it any more likely for plants to
B、 because it is genetically engineered does not make a plant any more likely to
C、 being genetically engineered does not make it any more likely that plants will
D、 being genetically engineered does not make a plant any more likely to
E、 being genetically engineered does not make a plant any more likely that it will become

答案:

D
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题目：

In 1713, Alexander Pope began his translation of the Iliad, a work that, taking him seven years until completion, and that literary critic Samuel Johnson, Pope’s contemporary, pronounced the greatest translation in any language.

选项:

A、his translation of the Iliad, a work that, taking him seven years until completion, and that literary critic Samuel Johnson, Pope’s contemporary, pronounced
B、his translation of the Iliad, a work that took him seven years to complete and that literary critic Samuel Johnson, Pope’s contemporary, pronounced
C、his translation of the Iliad, a work that had taken seven years to complete and that literary critic Samuel Johnson, Pope’s contemporary, pronounced it as
D、translating the Iliad, a work that took seven years until completion and that literary critic Samuel Johnson, Pope’s contemporary, pronounced it as
E、translating the Iliad, a work that had taken seven years to complete and literary critic Samuel Johnson, Pope’s contemporary, pronounced it

答案:

B
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[Critical Reasoning]

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题目：

With employer-paid training, workers have the potential to become more productive not only in their present employment but also in any number of jobs with different employers. To increase the productivity of their workforce, many firms are planning to maintain or even increase their investments in worker training. But some training experts object that if a trained worker is hired away by another firm, the employer that paid for the training has merely subsidized a competitor. They note that such hiring has been on the rise in recent years.

Which of the following would, if true, contribute most to defeating the training experts’ objection to the firms’ strategy?

选项:

答案:

E
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[Undefined]

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Art historian: Unlike many artistic traditions that sought to depict plants native to the local area in a seasonally appropriate way (for example, depicting scenes of spring with the plants in the appropriate stages of development for that season), seventeenth-century Dutch artists specializing in flower paintings almost exclusively chose to depict exotic species of flowers from outside the local area. Painting such species was worthwhile primarily because the art-buying public had developed a strong preference for images of the exotic. The great botanical centers of the time gave the artists direct access to such flowers, which the artists would freely combine in a single painting, regardless of whether the combined species occurred together in the wild, and depicted each in full bloom, regardless of whether those species bloomed at the same time in nature.

Statement: The art historian makes the point that the species of flowers these Dutch artists chose to paint were 1 largely because the species were 2 .

Select for 1 and for 2 the options that complete the statement so that it is most strongly supported by the information provided. Make only two selections, one in each column.
我选的CE，和EC有什么区别？怎么选出EC的？
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[Undefined]

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An unusually severe winter occurred in Europe after the continent was blanketed by a blue haze resulting from the eruption of the Laki Volcano in the European republic of Iceland in the summer of 1984.  Thus, it is evident that major eruptions cause the atmosphere to become cooler than it would be otherwise.
Which of the following statements, if true, most seriously weakens the argument above?
C选项为什么就不会有张冠李戴的问题呢，1984和1982的气候情况能一样吗，C里的火山就可以试用于原文的火山吗
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[Undefined]

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The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A present and inversely proportional to the concentration of chemical B present. If the concentration of chemical B is increased by 100 percent, which of the following is closest to the percent change in the concentration of chemical A required to keep the reaction rate unchanged?
为什么这个题一定是相乘不能是相加呢？y=k1A方-k2B （k1,k2大于0 ），也满足题目说的与A方成正比与B成反比啊？但是这道题只有相乘的情况才能选出正确答案
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[Undefined]

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Tiger beetles are such fast runners that they can capture virtually any nonflying insect.  However, when running toward an insect, the beetles intermittently stop, and then, a moment later, resume their attack.  Perhaps they cannot maintain their pace and must pause for a moment's rest; but an alternative hypothesis is that while running tiger beetles are unable to process the resulting rapidly changing visual information, and so quickly go blind and stop.
 
Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two hypotheses and undermine the other?
答案C是怎么支持一个猜想又削弱另一个猜想的？
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[GWD]

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The author of the passage implies that which of the following is a possible partial explanation for acquisition behavior during the 1970's and 1980's?
请解释这道题为什么不选C或E，除了正确选项B，我认为文中也正确地提到了这两个选项可以解释acquisition behavior during 1970s and 80s
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[OG]

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The primary purpose of the passage is to
为什么选E不选B
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[Undefined]

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Club X has more than 10 but fewer than 40 members. Sometimes the members sit at tables with 3 members at one table and 4 members at each of the other tables, and sometimes they sit at tables with 3 members at one table and 5 members at each of the other tables. If they sit at tables with 6 members at each table except one and fewer than 6 members at that one table, how many members will be at the table that has fewer than 6 members?
提问小梅老师 这道题求讲一下 我没什么思路 带入数字得的是3
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[Undefined]

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A photography dealer ordered 60 Model X cameras to be sold for $250 each, which represents a 20 percent markup over the dealer's initial cost for each camera. Of the cameras ordered, 6 were never sold and were returned to the manufacturer for a refund of 50 percent of the dealer's initial cost. What was the dealer's approximate profit or loss as a percent of the dealer's initial cost for the 60 cameras?
请问小梅老师 这道题讲讲一下 我算的是19% 原来成本是200每个 亏了6个 每个亏100. 最后得不出答案
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[Undefined]

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Analytical!
请问may老师，这题该用什么思路来做？
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[Undefined]

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Analytical!
请问张老师，这道题为什么D不对？我有我觉得second paragraph最后一句话特别指向D
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