问答

1答疑

[Reading Comprehension]

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文章：

Line Conodonts, the spiky phosphatic remains (bones
and teeth composed of calcium phosphate) of
tiny marine animals that probably appeared about
520 million years ago, were once among the most
(5) controversial of fossils. Both the nature of the
organism to which the remains belonged and the
function of the remains were unknown. However,
since the 1981 discovery of fossils preserving not
just the phosphatic elements but also other remains
(10) of the tiny soft-bodied animals (also called conodonts)
that bore them, scientists’ reconstructions of the
animals’ anatomy have had important implications
for hypotheses concerning the development of the
vertebrate skeleton.
(15) The vertebrate skeleton had traditionally been
regarded as a defensive development, champions of
this view postulating that it was only with the much
later evolution of jaws that vertebrates became
predators. The first vertebrates, which were soft-
(20) bodied, would have been easy prey for numerous
invertebrate carnivores, especially if these early
vertebrates were sedentary suspension feeders.
Thus, traditionalists argued, these animals developed
coverings of bony scales or plates, and teeth were
(25) secondary features, adapted from the protective
bony scales. Indeed, external skeletons of this
type are common among the well-known fossils of
ostracoderms, jawless vertebrates that existed from
approximately 500 to 400 million years ago.
(30) However, other paleontologists argued that many of
the definitive characteristics of vertebrates, such as
paired eyes and muscular and skeletal adaptations
for active life, would not have evolved unless the
first vertebrates were predatory. Teeth were more
(35) primitive than external armor according to this view,
and the earliest vertebrates were predators.
The stiffening notochord along the back of the
body, V-shaped muscle blocks along the sides,
and posterior tail fins help to identify conodonts as
(40) among the most primitive of vertebrates. The lack of
any mineralized structures apart from the elements
in the mouth indicates that conodonts were more
primitive than the armored jawless fishes such as the
ostracoderms. It now appears that the hard parts that
(45) first evolved in the mouth of an animal improved its
efficiency as a predator, and that aggression rather
than protection was the driving force behind the origin
of the vertebrate skeleton.

题目：

The second paragraph in the passage serves primarily to

选项:

A、outline the significance of the 1981 discovery of conodont remains to the debate concerning the development of the vertebrate skeleton
B、contrast the traditional view of the development of the vertebrate skeleton with a view derived from the 1981 discovery of conodont remains
C、contrast the characteristics of the ostracoderms with the characteristics of earlier soft-bodied vertebrates
D、explain the importance of the development of teeth among the earliest vertebrate predators
E、present the two sides of the debate concerning the development of the vertebrate skeleton

答案:

E
1答疑

[Data Sufficiency]

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题目：

Line ℓ lies in the xy-plane and does not pass through the origin. What is the slope of line ℓ ?
  1. The x-intercept of line ℓ is twice the y-intercept of line ℓ.
  2. The x- and y-intercepts of line ℓ are both positive.

选项:

A、Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B、Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C、BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D、EACH statement ALONE is sufficient.
E、Statements (1) and (2) TOGETHER are not sufficient.

答案:

A
1答疑

[Data Sufficiency]

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题目：

If a and b are constants, is the expression defined for x = –2 ?
  1. a = 5
  2. b = 6

选项:

A、Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B、Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C、BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D、EACH statement ALONE is sufficient.
E、Statements (1) and (2) TOGETHER are NOT sufficient.

答案:

A
1答疑

[Sentence Correction]

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题目：

Scientists who studied the famous gold field known as Serra Pelada concluded that the rich lode was not produced by the accepted methods of ore formation but that swarms of microbes over millions of years concentrated the gold from jungle soils and rivers and rocks.

选项:

A、not produced by the accepted methods of ore formation but that swarms of microbes over millions of years
B、not produced by the accepted methods of ore formation but instead swarms of microbes over millions of years that
C、not produced by the accepted methods of ore formation but swarms of microbes over millions of years that
D、produced not by the accepted methods of ore formation but by swarms of microbes that over millions of years
E、produced not by the accepted methods of ore formation but that swarms of microbes over millions of years

答案:

D
1答疑

[Critical Reasoning]

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题目：

Which of the following most logically completes the passage?

Pecan growers get a high price for their crop when pecans are comparatively scarce, but the price drops sharply when pecans are abundant. Thus, in high-yield years, growers often hold back part of their crop in refrigerated warehouses for one or two years, hoping for higher prices in the future. This year’s pecan crop was the smallest in five years. It is nonetheless quite possible that a portion of this year’s crop will be held back, since ________.

选项:

A、each of the last two years produced record-breaking pecan yields
B、the quality of this year’s pecan crop is no worse than the quality of the pecan crops of the previous five years
C、pecan prices have not been subject to sharp fluctuations in recent years
D、for some pecan growers, this year’s crop was no smaller than last year’s
E、the practice of holding back part of one year’s crop had not yet become widespread the last time the pecan crop was as small as it was this year

答案:

A
1答疑

[Reading Comprehension]

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文章：

题目：

The passage implies that which of the following is a possible consequence of a company's adoption of innovations that increase its ecoefficiency?

选项:

A、Company profits resulting from such innovations may be reinvested in that company with no guarantee that the company will continue to make further improvements in ecoefficiency.
B、Company growth fostered by cost savings from such innovations may allow that company to manufacture a greater number of products that will be used and discarded, thus worsening environmental stress.
C、A company that fails to realize significant cost savings from such innovations may have little incentive to continue to minimize the environmental impact of its production processes.
D、A company that comes to depend on such innovations to increase its profits and growth may be vulnerable in the global market to competition from old-style eco-inefficient industries.
E、A company that meets its ecoefficiency goals is unlikely to invest its increased profits in the development of new and innovative ecoefficiency measures.

答案:

B
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[Sentence Correction]

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题目：

A professor at the university has taken a sabbatical to research on James Baldwin's books that Baldwin wrote in France while he was living there.

选项:

A、on James Baldwin's books that Baldwin wrote in France while he was living there
B、about the books James Baldwin wrote in France
C、into James Baldwin's books written while in France
D、on the books of James Baldwin, written while he lived in France
E、the books James Baldwin wrote while he lived in France

答案:

E
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[Sentence Correction]

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题目：

Some biographers have not only disputed the common notion that Edgar Allan Poe drank to excess but also questioned whether he drank at all.

选项:

A、have not only disputed the common notion that Edgar Allan Poe drank to excess but also questioned whether he drank
B、not only have disputed the common notion that Edgar Allan Poe drank to excess but also over whether he drank
C、have disputed not only the common notion that Edgar Allan Poe drank to excess but also whether he may not have drunk
D、not only have disputed the common notion that Edgar Allan Poe drank to excess but also questioned whether or not he had drunk
E、have disputed the common notion not only that Edgar Allan Poe drank to excess but also questioned whether he may not have drunk

答案:

A
1答疑

[Problem Solving]

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题目：

A certain right triangle has sides of length x, y, and z, where x < y < z. If the area of this triangular region is 1, which of the following indicates all of the possible values of y ?

选项:

A、
B、
C、
D、
E、

答案:

A
1答疑

[Data Sufficiency]

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题目：

The total cost of an office dinner was shared equally by k of the n employees who attended the dinner. What was the total cost of the dinner?
(1)   Each of the k employees who shared the cost of the dinner paid $19.
(2)   If the total cost of the dinner had been shared equally by k + 1 of the n employees who attended the dinner, each of the k + 1 employees would have paid $18.

选项:

答案:

C
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369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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1349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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1521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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585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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1355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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963浏览

[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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645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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655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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161979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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