问答

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[Reading Comprehension]

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文章：

    In the 1930's and 1940's, African American industrial workers in the southern United States, who constituted 80 percent of the unskilled factory labor force there, strongly supported unionization. While the American Federation of Labor (AFL) either excluded African Americans or maintained racially segregated unions, the Congress of Industrial Organizations (CIO) organized integrated unions nationwide on the basis of a stated policy of equal rights for all, and African American unionists provided the CIO's backbone. Yet it can be argued that through contracts negotiated and enforced by White union members, unions—CIO unions not excluded—were often instrumental in maintaining the occupational segregation and other forms of racial discrimination that kept African Americans socially and economically oppressed during this period. However, recognizing employers' power over workers as a central factor in African Americans' economic marginalization, African American workers saw the need to join with White workers in seeking change despite White unionists' toleration of or support for racial discrimination. The persistent efforts of African American unionists eventually paid off: many became highly effective organizers, gaining the respect of even racist White unionists by winning victories for White as well as African American workers. African American unionists thus succeeded in strengthening the unions while using them as instruments of African Americans' economic empowerment.

题目：

According to the passage, which of the following was true of many racist White unionists during the period discussed in the passage?

选项:

A、Their attitudes toward African American union organizers changed once they recognized that the activities of these organizers were serving workers' interests.
B、They were a powerful element in the southern labor movement because they constituted the majority of the unskilled factory labor force in the southern United States.
C、They persisted in opposing the CIO's adoption of a stated policy of equal rights for all.
D、Their primary goal was to strengthen the negotiating power of the unions through increasing White union membership.
E、Their advocacy of racial discrimination hampered unions in their efforts to gain more power for workers.

答案:

A
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[Problem Solving]

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题目：

In a meeting of 3 representatives from each of 6 different companies, each person shook hands with every person not from his or her own company. If the representatives did not shake hands with people from their own company, how many handshakes took place?

选项:

A、45
B、135
C、144
D、270
E、288

答案:

B
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[Data Sufficiency]

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题目：

What is the median number of employees assigned per project for the projects at Company Z?
(1)   25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project.

选项:

答案:

C
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[Sentence Correction]

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题目：

Japanese researchers are producing a series of robots that can identify human facial expressions, to which they will then respond; their goal is primarily creating a robot that will empathize with us.

选项:

A、 expressions, to which they will then respond; their goal is primarily creating
B、 expressions, then responding to them; primarily to create
C、 expressions and then respond to them; the researchers' primary goal is to create
D、 expressions as well as giving a response to them; their primary goal is creation of
E、 expressions and responding to them; primarily, the researchers' goal is creating

答案:

C
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[Sentence Correction]

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题目：

Elizabeth Barber, the author of both Prehistoric Textiles, a comprehensive work on cloth in the early cultures of the Mediterranean, and also of Women's Work, a more general account of early cloth manufacture, is an expert authority on textiles in ancient societies.

选项:

A、also of Women's Work, a more general account of early cloth manufacture, is an expert authority on
B、also Women's Work, a more general account of cloth manufacture, is an expert authority about
C、of Women's Work, a more general account about early cloth manufacture, is an authority on
D、of Women's Work, a more general account about early cloth manufacture, is an expert authority about
E、Women's Work, a more general account of early cloth manufacture, is an authority on

答案:

E
2答疑

[Reading Comprehension]

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文章：

Line         A small number of the forest species of
  lepidoptera (moths and butterflies, which exist as
  caterpillars during most of their life cycle) exhibit
  regularly recurring patterns of population growth
(5) and decline—such fluctuations in population are
  known as population cycles. Although many different
  variables influence population levels, a regular pattern
  such as a population cycle seems to imply a
  dominant, driving force. Identification of that driving
(10) force, however, has proved surprisingly elusive
  despite considerable research. The common
  approach of studying causes of population cycles by
  measuring the mortality caused by different agents,
  such as predatory birds or parasites, has been
(15) unproductive in the case of lepidoptera. Moreover,
  population ecologists’ attempts to alter cycles by
  changing the caterpillars’ habitat and by reducing
  caterpillar populations have not succeeded. In short,
  the evidence implies that these insect populations, if
(20) not self-regulating, may at least be regulated by an
  agent more intimately connected with the insect than
  are predatory birds or parasites.
       Recent work suggests that this agent may be a
  virus. For many years, viral disease had been reported
(25) in declining populations of caterpillars, but population
  ecologists had usually considered viral disease to
  have contributed to the decline once it was underway
  rather than to have initiated it. The recent work has
  been made possible by new techniques of molecular
(30) biology that allow viral DNA to be detected at low
  concentrations in the environment. Nuclear
  polyhedrosis viruses are hypothesized to be the
  driving force behind population cycles in lepidoptera
  in part because the viruses themselves follow an
(35) infectious cycle in which, if protected from direct
  sun light, they may remain virulent for many years
  in the environment, embedded in durable crystals of
  polyhedrin protein. Once ingested by a caterpillar,
  the crystals dissolve, releasing the virus to infect
(40) the insect’s cells. Late in the course of the infection,
  millions of new virus particles are formed and
  enclosed in polyhedrin crystals. These crystals
  reenter the environment after the insect dies and
  decomposes, thus becoming available to infect
(45) other caterpillars.
       One of the attractions of this hypothesis is its broad
  applicability. Remarkably, despite significant differences
  in habitat and behavior, many species of lepidoptera
  have population cycles of similar length, between eight
(50) and eleven years. Nuclear polyhedrosis viral infection is
  one factor these disparate species share.


题目：

Which of the following, if true, would most weaken the author’s conclusion in lines 18–22 ?

选项:

A、New research reveals that the number of species of birds and parasites that prey on lepidoptera has dropped significantly in recent years.
B、New experiments in which the habitats of lepidoptera are altered in previously untried ways result in the shortening of lepidoptera population cycles.
C、Recent experiments have revealed that the nuclear polyhedrosis virus is present in a number of predators and parasites of lepidoptera.
D、Differences among the habitats of lepidoptera species make it difficult to assess the effects of weather on lepidoptera population cycles.
E、Viral disease is typically observed in a large proportion of the lepidoptera population.

答案:

B
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[Reading Comprehension]

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文章：

Line         There are recent reports of apparently drastic
  declines in amphibian populations and of extinctions
  of a number of the world’s endangered amphibian
  species. These declines, if real, may be signs of a
(5) general trend toward extinction, and many
  environmentalists have claimed that immediate
  environmental action is necessary to remedy
  this “amphibian crisis,” which, in their view, is an
  indicator of general and catastrophic environmental
(10) degradation due to human activity.
       To evaluate these claims, it is useful to make a
  preliminary distinction that is far too often ignored.
  A declining population should not be confused with
  an endangered one. An endangered population is
(15) always rare, almost always small, and, by definition,
  under constant threat of extinction even without a
  proximate cause in human activities. Its disappearance,
  however unfortunate, should come as no great
  surprise. Moreover, chance events—which may
(20) indicate nothing about the direction of trends in
  population size—may lead to its extinction. The
  probability of extinction due to such random factors
  depends on the population size and is independent of
  the prevailing direction of change in that size.
(25)      For biologists, population declines are potentially
  more worrisome than extinctions. Persistent
  declines, especially in large populations, indicate a
  changed ecological context. Even here, distinctions
  must again be made among declines that are only
(30) apparent (in the sense that they are part of habitual
  cycles or of normal fluctuations), declines that take
  a population to some lower but still acceptable
  level, and those that threaten extinction (e.g., by
  taking the number of individuals below the minimum
(35) viable population). Anecdotal reports of population
  decreases cannot distinguish among these
  possibilities, and some amphibian populations have
  shown strong fluctuations in the past.
       It is indisputably true that there is simply not
(40) enough long-term scientific data on amphibian
  populations to enable researchers to identify real
  declines in amphibian populations. Many fairly
  common amphibian species declared all but extinct
  after severe declines in the 1950s and 1960s
(45) have subsequently recovered, and so might
  the apparently declining populations that have
  generated the current appearance of an amphibian
  crisis. Unfortunately, long-term data will not soon
  be forthcoming, and postponing environmental
(50) action while we wait for it may doom species and
  whole ecosystems to extinction.


题目：

It can be inferred from the passage that the author believes which of the following to be true of the amphibian extinctions that have recently been reported?

选项:

A、They have resulted primarily from human activities causing environmental degradation.
B、They could probably have been prevented if timely action had been taken to protect the habitats of amphibian species.
C、They should not come as a surprise, because amphibian populations generally have been declining for a number of years.
D、They have probably been caused by a combination of chance events.
E、They do not clearly constitute evidence of general environmental degradation.

答案:

E
2答疑

[Reading Comprehension]

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文章：

Line         Manufacturers have to do more than build large
  manufacturing plants to realize economies of scale.
  It is true that as the capacity of a manufacturing
  operation rises, costs per unit of output fall as plant
(5) size approaches “minimum efficient scale,” where the
  cost per unit of output reaches a minimum,
  determined roughly by the state of existing technology
  and size of the potential market. However, minimum
  efficient scale cannot be fully realized unless a steady
(10) “throughput” (the flow of materials through a plant) is
  attained. The throughput needed to maintain the
  optimal scale of production requires careful
  coordination not only of the flow of goods through the
  production process, but also of the flow of input from
(15) suppliers and the flow of output to wholesalers and
  final consumers. If throughput falls below a critical
  point, unit costs rise sharply and profits disappear. A
  manufacturer’s fixed costs and “sunk costs” (original
  capital investment in the physical plant) do not
(20) decrease when production declines due to inadequate
  supplies of raw materials, problems on the factory
  floor, or inefficient sales networks. Consequently,
  potential economies of scale are based on the
  physical and engineering characteristics of the
(25) production facilities—that is, on tangible capital—but
  realized economies of scale are operational and
  organizational, and depend on knowledge, skills,
  experience, and teamwork—that is, on organized
  human capabilities, or intangible capital.
(30)      The importance of investing in intangible capital
  becomes obvious when one looks at what happens in
  new capital-intensive manufacturing industries. Such
  industries are quickly dominated, not by the first firms
  to acquire technologically sophisticated plants of
(35) theoretically optimal size, but rather by the first to
  exploit the full potential of such plants. Once some
  firms achieve this, a market becomes extremely hard
  to enter. Challengers must construct comparable
  plants and do so after the first movers have already
(40) worked out problems with suppliers or with new
  production processes. Challengers must create
  distribution networks and marketing systems in
  markets where first movers have all the contacts and
  know-how. And challengers must recruit management
(45) teams to compete with those that have already
  mastered these functional and strategic activities.


题目：

The passage LEAST supports the inference that a manufacturer’s throughput could be adversely affected by

选项:

A、a mistake in judgment regarding the selection of a wholesaler
B、a breakdown in the factory’s machinery
C、a labor dispute on the factory floor
D、an increase in the cost per unit of output
E、a drop in the efficiency of the sales network

答案:

D
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[Sentence Correction]

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题目：

Rock samples taken from the remains of an asteroid about twice the size of the 6-mile-wide asteroid that eradicated the dinosaurs has been dated to be 3.47 billion years old and thus is evidence of the earliest known asteroid impact on Earth.

选项:

A、has been dated to be 3.47 billion years old and thus is
B、has been dated at 3.47 billion years old and thus
C、have been dated to be 3.47 billion years old and thus are
D、have been dated as being 3.47 billion years old and thus
E、have been dated at 3.47 billion years old and thus are

答案:

E
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[Critical Reasoning]

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题目：

Criminologist:  Some legislators advocate mandating a sentence of life in prison for anyone who, having twice served sentences for serious crimes, is subsequently convicted of a third serious crime.  These legislators argue that such a policy would reduce crime dramatically, since it would take people with a proven tendency to commit crimes off the streets permanently.  What this reasoning overlooks, however, is that people old enough to have served two prison sentences for serious crimes rarely commit more than one subsequent crime.  Filling our prisons with such individuals would have exactly the opposite of the desired effect, since it would limit our ability to incarcerate younger criminals, who commit a far greater proportion of serious crimes.
 
In the argument as a whole, the two boldfaced portions play which of the following roles?

选项:

A、The first is a conclusion that the argument as a whole seeks to refute; the second is a claim that has been advanced in support of that conclusion.
B、The first is a conclusion that the argument as a whole seeks to refute; the second is the main conclusion of the argument.
C、The first is the main conclusion of the argument; the second is an objection that has been raised against that conclusion.
D、The first is the main conclusion of the argument; the second is a prediction made on the basis of that conclusion.
E、The first is a generalization about the likely effect of a policy under consideration in the argument; the second points out a group of exceptional cases to which that generalization does not apply.

答案:

B
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393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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1411浏览

[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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601浏览

[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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1403浏览

[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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657浏览

[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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673浏览

[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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165236浏览

[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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