问答

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[Critical Reasoning]

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题目：

A diet high in saturated fats increases a person's risk of developing heart disease.  Regular consumption of red wine reduces that risk.  Per-capita consumption of saturated fats is currently about the same in France as in the United States, but there is less heart disease there than in the United States because consumption of red wine is higher in France.  The difference in regular red-wine consumption has been narrowing, but no similar convergence in heart-disease rates has occurred.
 
Which of the following, if true, most helps to account for the lack of convergence noted above?

选项:

A、Consumption of saturated fats is related more strongly to the growth of fatty deposits on artery walls, which reduce blood flow to the heart, than it is to heart disease directly.
B、Over the past 30 years, per-capita consumption of saturated fats has remained essentially unchanged in the United States but has increased somewhat in France.
C、Reports of the health benefits of red wine have led many people in the United States to drink red wine regularly.
D、Cigarette smoking, which can also contribute to heart disease, is only slightly more common in France than in the United States.
E、Regular consumption of red wine is declining dramatically among young adults in France, and heart disease typically does not manifest itself until middle age.

答案:

E
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[Data Sufficiency]

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题目：

If x is a positive integer, is the remainder 0 when (3x + 1)/10?
(1)     x = 3n + 2, where n is a positive integer.
(2)     x > 4

选项:

答案:

E
3答疑

[Reading Comprehension]

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文章：

    Years before the advent of plate tectonics―the widely accepted theory, developed in the mid-1960's, the holds that the major features of Earth's surface are created by the horizontal motions of Earth's outer shell, or lithosphere a similar theory was rejected by the geological community. In 1912, Alfred Wegener proposed, in a widely debate theory that came to be called continental drift, that Earth's continents were mobile. To most geologists today, Wegener's The origin of Continents and Oceans appears an impressive and prescient document, containing several of the essential presumptions underlying plate tectonics theory: the horizontal mobility of pieces of Earth's crust; the essential difference between oceanic and conti nental crust; and a causal connection between horizontal displacements and the formation of mountain chains. Yet despite the considerable overlap between Wegener's concepts and the later widely embraced plate tectonics theory, and despite the fact that continental drift theory presented a possible solution to the problem of the origin of mountains at a time when existing explanations were seriously in doubt, in its day Wegener's theory was rejected by the vast majority of geologists.

    Most geologists and many historians today believe that Wegener's theory was rejected because of its lack of an adequate mechanical basis. Stephen Jay Gould, for example, argues that continental drift theory was rejected because it did not explain how continent could move through an apparently solid oceanic floor. However, as Anthony Hallam has pointed out, many scientific phenomena, such as the ice ages, have been accepted before they could be fully explained. The most likely cause for the rejection of continental drift―a cause that has been largely ignored because we consider Wegener's theory to have been validated by the theory of plate tectonics―is the nature of the evidence that was put forward to support it. Most of Wegener's evidence consisted of homologies-similarities of patterns and forms based on direct observations of rocks in the field, supported by the use of hammers, hand lenses, and field notebooks. In contrast, the data supporting plate tectonics were impressively geophysical-instrumental determinations of the physical properties of Earth garnered through the use of seismographs, magnetometers, and computers.

题目：

The author of the passage refers to the "considerable overlap" (in the highlighted text) between continental drift theory and plate tectonics theory most probably in order to

选项:

A、suggest that plate tectonics theory is derived from Wegener's work
B、introduce a discussion comparing the elements of the two theories
C、examine the question of whether continental drift theory was innovative in its time
D、provide a reason why it might seem surprising that continental drift theory was not more widely embraced by geologists
E、cite an explanation that has been frequently offered for Wegener's high standing among geologists today

答案:

D
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[Data Sufficiency]

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题目：

In planning for a trip, Joan estimated both the distance of the trip, in miles, and her average speed, in miles per hour. She accurately divided her estimated distance by her estimated average speed to obtain an estimate for the time, in hours, that the trip would take.  Was her estimate within 0.5 hour of the actual time that the trip took?
(1) Joan's estimate for the distance was within 5 miles of the actual distance.
(2)   Joan's estimate for her average speed was within 10 miles per hour of her actual average speed.

选项:

答案:

E
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[Reading Comprehension]

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文章：

Line         Milankovitch proposed in the early twentieth
  century that the ice ages were caused by variations
  in the Earth’s orbit around the Sun. For some time
  this theory was considered untestable, largely
(5) because there was no sufficiently precise
  chronology of the ice ages with which the orbital
  variations could be matched.
       To establish such a chronology it is necessary to
  determine the relative amounts of land ice that
(10) existed at various times in the Earth’s past. A
  recent discovery makes such a determination
  possible: relative land-ice volume for a given period
  can be deduced from the ratio of two oxygen
  isotopes, 16 and 18, found in ocean sediments.
(15) Almost all the oxygen in water is oxygen 16, but a
  few molecules out of every thousand incorporate the
  heavier isotope 18. When an ice age begins, the
  continental ice sheets grow, steadily reducing the
  amount of water evaporated from the ocean that
(20) will eventually return to it. Because heavier
  isotopes tend to be left behind when water
  evaporates from the ocean surfaces, the remaining
  ocean water becomes progressively enriched in
  oxygen 18. The degree of enrichment can be
(25) determined by analyzing ocean sediments of the
  period, because these sediments are composed of
  calcium carbonate shells of marine organisms,
  shells that were constructed with oxygen atoms
  drawn from the surrounding ocean. The higher the
(30) ratio of oxygen 18 to oxygen 16 in a sedimentary
  specimen, the more land ice there was when the
  sediment was laid down.
       As an indicator of shifts in the Earth’s climate,
  the isotope record has two advantages. First, it is a
(35) global record: there is remarkably little variation in
  isotope ratios in sedimentary specimens taken from
  different continental locations. Second, it is a
  more continuous record than that taken from rocks
  on land. Because of these advantages, sedimentary
(40) evidence can be dated with sufficient accuracy
  by radiometric methods to establish a precise
  chronology of the ice ages. The dated isotope
  record shows that the fluctuations in global ice
  volume over the past several hundred thousand
(45) years have a pattern: an ice age occurs roughly once
  every 100,000 years. These data have established
  a strong connection between variations in the Earth’s
  orbit and the periodicity of the ice ages.
       However, it is important to note that other
(50) factors, such as volcanic particulates or variations
  in the amount of sunlight received by the Earth,
  could potentially have affected the climate. The
  advantage of the Milankovitch theory is that it
  is testable; changes in the Earth’s orbit can be
(55) calculated and dated by applying Newton’s laws of
  gravity to progressively earlier configurations of the
  bodies in the solar system. Yet the lack of
  information about other possible factors affecting
  global climate does not make them unimportant.


题目：

It can be inferred from the passage that the isotope record taken from ocean sediments would be less useful to researchers if which of the following were true?

选项:

A、It indicated that lighter isotopes of oxygen predominated at certain times.
B、It had far more gaps in its sequence than the record taken from rocks on land.
C、It indicated that climate shifts did not occur every 100,000 years.
D、It indicated that the ratios of oxygen 16 and oxygen 18 in ocean water were not consistent with those found in fresh water.
E、It stretched back for only a million years.

答案:

B
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[Sentence Correction]

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题目：

Next month, state wildlife officials are scheduled to take over the job of increasing the wolf population in the federally designated recovery area, the number of which will however ultimately be dictated by the number of prey in the area.

选项:

A、area, the number of which will however
B、area; the size of the population, however, will
C、area, however the number of wolves will
D、area; the number of which will, however,
E、area, when the size of the population will, however,

答案:

B
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[Critical Reasoning]

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题目：

Political advocacy groups have begun to use information services to disseminate information that is then accessed by the public via personal computer.  Since many groups are thus able to bypass traditional news sources, whose reporting is selective, and to present their political views directly to the public, information services present a more balanced picture of the complexities of political issues than any traditional news source presents.
 
Which of the following is an assumption on which the argument above depends?

选项:

A、Information services are accessible to enough people to ensure that political advocacy groups can use these services to reach as large a percentage of the public as they could through traditional news sources.
B、People could get a thorough understanding of a particular political issue by sorting through information provided by several traditional news sources, each with differing editorial biases.
C、Information on political issues disseminated through information services does not come almost entirely from advocacy groups that share a single bias.
D、Traditional news sources seldom report the views of political advocacy groups accurately.
E、Most people who get information on political issues from newspapers and other traditional news sources can readily identify the editorial biases of those sources.

答案:

C
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[Sentence Correction]

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题目：

Linking arrangements among secondary schools and the workplace never evolved in the United States as they have in most other developed countries.

选项:

A、among secondary schools and the workplace never evolved in the United States as they have
B、in the United States among secondary schools and the workplace never evolved as they did
C、between secondary schools and the workplace never evolved in the United States as
D、in the United States between secondary schools and the workplace never evolved as they have
E、between secondary schools and the workplace never evolved in the United States as they did

答案:

E
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[Data Sufficiency]

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题目：

If x + y  is an integer, is y  an integer?
(1)     x – y  is an integer.
(2)     x + 2y  is an integer.

选项:

答案:

B
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[Sentence Correction]

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题目：

It may someday be worthwhile to try to recover uranium from seawater, but at present this process is prohibitively expensive.

选项:

A、It may someday be worthwhile to try to recover uranium from seawater
B、Someday, it may be worthwhile to try and recover uranium from seawater
C、Trying to recover uranium out of seawater may someday be worthwhile
D、To try for the recovery of uranium out of seawater may someday be worthwhile
E、Recovering uranium from seawater may be worthwhile to try to do someday

答案:

A
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791浏览

[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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2635浏览

[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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