问答

1答疑

[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：

Of the following topics, which would be most likely to be studied within the discipline of chemical ecology as it is described in the passage?

选项:

A、Seeds that become attached to certain insects, which in turn carry away the seeds and aid in the reproductive cycle of the plant species in question
B、An insect species that feeds on weeds detrimental to crop health and yield, and how these insects might aid in agricultural production
C、The effects of deforestation on the life cycles of subtropical carnivorous plants and the insect species on which the plants feed
D、The growth patterns of a particular species of plant that has proved remarkably resistant to herbicides
E、Insects that develop a tolerance for feeding on a plant that had previously been toxic to them, and the resultant changes within that plant species

答案:

E
1答疑

[Problem Solving]

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文章：


题目：

A car dealer sold x used cars and y new cars during May. If the number of used cars sold was 10 greater than the number of new cars sold, which of the following expresses this relationship?

选项:

A、x＞ lOyx＞ y + 10
B、x＞ y - 10
C、x= y + 10
D、x= y - 10

答案:

D
1答疑

[Sentence Correction]

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题目：

A long-term study of some 1,000 physicians indicates that the more coffee these doctors drank, the more they had a likelihood of coronary disease.

选项:

A、more they had a likelihood of coronary disease
B、more was their likelihood of having coronary disease
C、more they would have a likelihood to have coronary disease
D、greater was their likelihood of having coronary disease
E、greater was coronary disease likely

答案:

D
1答疑

[Data Sufficiency]

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题目：

If X and Y are points in a plane and X lies inside the circle C with center 0 and radius 2, does Y lie inside circle C ?
(1) The length of line segment XY is 3.
(2) The length of line segment OY is 1.5.

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:

B
1答疑

[Critical Reasoning]

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题目：

Prolonged spells of hot, dry weather at the end of the grape-growing season typically reduce a vineyard’s yield, because the grapes stay relatively small. In years with such weather, wine producers can make only a relatively small quantity of wine from a given area of vineyards. Nonetheless, in regions where wine producers generally grow their own grapes, analysts typically expect a long, hot, dry spell late in the growing season to result in increased revenues for local wine producers.

Which of the following, if true, does most to justify the analysts’ expectation?

选项:

A、The lower a vineyard’s yield, the less labor is required to harvest the grapes.
B、Long, hot, dry spells at the beginning of the grape-growing season are rare, but they can have a devastating effect on a vineyard’s yield.
C、Grapes grown for wine production are typically made into wine at or near the vineyard in which they were grown.
D、When hot, dry spells are followed by heavy rains, the rains frequently destroy grape crops.
E、Grapes that have matured in hot, dry weather make significantly better wine than ordinary grapes.

答案:

E
1答疑

[Data Sufficiency]

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题目：

  Number Studying
Biology 		Number Not
Studying Biology 		Total
Number
of Boys 		    18
Number
of Girls 		     
Total 26    

The table above shows the number of students in a certain high school class who are boys and the number of students in the class who are studying biology. What is the total number of students in the class?

(1)   Of the boys in the class, 15 are studying biology.
(2)   The number of girls in the class is twice the number of students in the class who are not studying biology.

选项:

答案:

B
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[Problem Solving]

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题目：

The diagram shows a shaded 9-sided polygon and 9 unshaded isosceles triangles. For each isosceles triangle, the longest side is a side of the shaded polygon and the two sides of equal length are extensions of the two adjacent sides of the shaded polygon.

The figure shown above consists of a shaded 9-sided polygon and 9 unshaded isosceles triangles. For each isosceles triangle, the longest side is a side of the shaded polygon and the two sides of equal length are extensions of the two adjacent sides of the shaded polygon. What is the value of a ?

选项:

A、100
B、105
C、110
D、115
E、120

答案:

A
1答疑

[Data Sufficiency]

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题目：

For a convention, a hotel charges a daily room rate of $120 for 1 person and x dollars for each additional person.  What is the charge for each additional person?
(1)     The daily cost per person for 4 people sharing the cost of a room equally is $45.
(2)   The daily cost per person for 2 people sharing the cost of a room equally is $25 more than the corresponding cost for 4 people.

选项:

答案:

D
1答疑

[Data Sufficiency]

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题目：

If the average (arithmetic mean) of four different numbers is 30, how many of the numbers are greater than 30?
(1)     None of the four numbers is greater than 60.
(2)     Two of the four numbers are 9 and 10, respectively.

选项:

答案:

C
1答疑

[Problem Solving]

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题目：

In the xy-plane, the points (c, d ) , (c, -d ), and (-c, -d ) are three vertices of a certain square. If and , which of the following points is in the same quadrant as the fourth vertex of the square?

选项:

A、(-5, -3)
B、(-5, 3)
C、(5, -3)
D、(3, -5)
E、(3, 5)

答案:

E
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390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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1397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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1564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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599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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1391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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981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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653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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670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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157539浏览

[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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164648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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