问答

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[Sentence Correction]

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题目：

About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.

选项:

答案:

B
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[Reading Comprehension]

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文章：

Line        Resin is a plant secretion that hardens when
 exposed to air; fossilized resin is called amber.
 Although Pliny in the first century recognized that
 amber was produced from “marrow discharged by
(5)trees,” amber has been widely misunderstood to be
 a semiprecious gem and has even been described
 in mineralogy textbooks. Confusion also persists
 surrounding the term “resin,” which was defined
 before rigorous chemical analyses were available.
(10)Resin is often confused with gum, a substance
 produced in plants in response to bacterial infections,
 and with sap, an aqueous solution transported
 through certain plant tissues. Resin differs from both
 gum and sap in that scientists have not determined a
(15)physiological function for resin.
      In the 1950s, entomologists posited that resin
 may function to repel or attract insects. Fraenkel
 conjectured that plants initially produced resin in
 nonspecific chemical responses to insect attack
(20)and that, over time, plants evolved that produced
 resin with specific repellent effects. But some insect
 species, he noted, might overcome the repellent
 effects, actually becoming attracted to the resin.
 This might induce the insects to feed on those
(25)plants or aid them in securing a breeding site.
 Later researchers suggested that resin mediates
 the complex interdependence, or “coevolution,” of
 plants and insects over time. Such ideas led to the
 development of the specialized discipline of chemical
(30)ecology, which is concerned with the role of plant
 chemicals in interactions with other organisms and
 with the evolution and ecology of plant antiherbivore
 chemistry (plants' chemical defenses against attack
 by herbivores such as insects).


题目：

The author refers to “bacterial infections” (see line 11) most likely in order to

选项:

A、to both its introduction of new models in North America that are less expensive in their manufacture and to success in
B、to both its introduction of new models in North America that are less expensive in manufacturing and success in its
C、to both its introducing new models in North America that are less expensive in manufacturing and to success in
D、both to its introduction of new models in North America that are less expensive to manufacture and to success in
E、both to its introducing new models in North America that are less expensive in their manufacturing and to success in its

答案:

A
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[Sentence Correction]

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题目：

While most of the earliest known ball courts in Mesoamerica date to 900–400 b.c., waterlogged latex balls found at El Manati and representations of ballplayers painted on ceramics found at San Lorenzo attest to the fact that the Mesoamerican ballgame was well established by the mid-thirteenth century b.c.

选项:

答案:

A
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[Reading Comprehension]

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Traditional social science models of class groups in the United States are based on economic status and assume that women's economic status derives from association with men, typically fathers or husbands, and that women therefore have more compelling common interest with men of their own economic class than with women outside it.  Some feminist social scientists, by contrast, have argued that the basic division in American society is instead based on gender, and that the total female population, regardless of economic status, constitutes a distinct class.  Social historian Mary Ryan, for example, has argued that in early-nineteenth-century America the identical legal status of working-class and middle-class free women outweighed the differences between women of these two classes:  married women, regardless of their family's wealth, did essentially the same unpaid domestic work, and none could own property or vote.  Recently, though, other feminist analysts have questioned this model, examining ways in which the condition of working-class women differs from that of middle-class women as well as from that of working-class men.  Ann Oakley notes, for example, that the gap between women of different economic classes widened in the late nineteenth century:  most working-class women, who performed wage labor outside the home, were excluded from the emerging middle-class ideal of femininity centered around domesticity and volunteerism.

题目：

It can be inferred from the passage that the most recent feminist social science research on women and class seeks to do which of the following?

选项:

A、Introduce a divergent new theory about the relationship between legal status and gender
B、Illustrate an implicit middle-class bias in earlier feminist models of class and gender
C、Provide evidence for the position that gender matters more than wealth in determining class status
D、Remedy perceived inadequacies of both traditional social science models and earlier feminist analyses of class and gender
E、Challenge the economic definitions of class used by traditional social scientists

答案:

D
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[Reading Comprehension]

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文章：

    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 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 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 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 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 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 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 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 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 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 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 the highlighted text?

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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[Critical Reasoning]

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题目：

For similar cars and drivers, automobile insurance for collision damage has always cost more in Greatport than in Fairmont.  Police studies, however, show that cars owned by Greatport residents are, on average, slightly less likely to be involved in a collision than cars in Fairmont.  Clearly, therefore, insurance companies are making a greater profit on collision-damage insurance in Greatport than in Fairmont.
 
Which of the following is an assumption on which the argument depends?

选项:

A、Repairing typical collision damage does not cost more in Greatport than in Fairmont.
B、There are no more motorists in Greatport than in Fairmont.
C、Greatport residents who have been in a collision are more likely to report it to their insurance company than Fairmont residents are.
D、Fairmont and Greatport are the cities with the highest collision-damage insurance rates.
E、The insurance companies were already aware of the difference in the likelihood of collisions before the publication of the police reports.

答案:

A
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[Critical Reasoning]

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题目：

Which of the following most logically completes the argument?
Utrania was formerly a major petroleum exporter, but in recent decades economic stagnation and restrictive regulations inhibited investment in new oil fields.  In consequence, Utranian oil exports dropped steadily as old fields became depleted.  Utrania's currently improving economic situation, together with less-restrictive regulations, will undoubtedly result in the rapid development of new fields.  However, it would be premature to conclude that the rapid development of new fields will result in higher oil exports, because __________.

选项:

A、the price of oil is expected to remain relatively stable over the next several years
B、the improvement in the economic situation in Utrania is expected to result in a dramatic increase in the proportion of Utranians who own automobiles
C、most of the investment in new oil fields in Utrania is expected to come from foreign sources
D、new technology is available to recover oil from old oil fields formerly regarded as depleted
E、many of the new oil fields in Utrania are likely to be as productive as those that were developed during the period when Utrania was a major oil exporter

答案:

B
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[Sentence Correction]

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题目：

Some anthropologists regard the early hominids' manner of walking as being less efficient than in modern human beings.

选项:

A、as being less efficient than in
B、as less efficient than it is in
C、as less efficient than that of
D、to be less efficient than that of
E、to have been less efficient than it is in

答案:

C
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[Critical Reasoning]

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题目：

Kirkland’s theory of corporate structure can be represented by a truncated pyramid. There are workers, middle management, and executive management, but no head of the corporation. Instead, all major decisions are made by committee. As a consequence, in Kirkland’s structure, risky, cutting-edge technologies cannot be developed.
Which one of the following is an assumption on which the argument depends?

选项:

A、A. Cutting-edge technologies are typically developed by entrepreneurs, not by big corporations.
B、B. Only single individuals will make risky decisions.
C、C. An individual is more likely to take a gamble on his own than in a group.
D、D. All heads of corporations reached their positions by taking risks.
E、E. All cutting-edge technologies involve some risk.

答案:

B
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[Sentence Correction]

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题目：

Along the major rivers that traverse the deserts of northeast Africa, the Middle East, and northwest India, the combination of a reliable supply of water and good growing conditions both encouraged farming traditions that, in places, endure in at least 6,000 years.

选项:

A、good growing conditions both encouraged farming traditions that, in places, endure in
B、good growing conditions encouraged farming traditions that have, in places, endured for
C、of good growing conditions have encouraged farming traditions that, in places, endured for
D、of good growing conditions both encouraged farming traditions that have, in places, endured
E、of good growing conditions encouraged farming traditions that have, in places, been enduring for

答案:

B
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945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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2752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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[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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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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