问答

1答疑

[Sentence Correction]

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题目：

 Displays of the aurora borealis, or ''northern lights” can heat the atmosphere over the arctic enough to affect the trajectories of ballistic missiles, induce electric currents that can cause blackouts in some areas and corrosion in north-south pipelines.

选项:

A、to affect the trajectories of ballistic missiles, induce 
B、that the trajectories of ballistic missiles are affected, induce 
C、that it affects the trajectories of ballistic missiles, induces 
D、that the trajectories of ballistic missiles are affected and induces 
E、to affect the trajectories of ballistic missiles and induce

答案:

E
1答疑

[Graphics Interpretation]

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题目：

The flowchart represents a mathematical algorithm that takes two positive integers as the input and returns a positive integer as the output. Processes are indicated in the rectangular symbols in the flowchart. Each process is symbolized by an equation, such as T = T +a. In this particular process, the current values of the variables T and a are added together and the sum then becomes the value of T. For example, if the value ofT is 3 and the value of a is 7 before the process T = T +ais completed, then the value of T is 10 and the value of a is 7 after the process is completed.
Use the drop-down menus to fill in the blanks in the following statements based on the algorithm represented by the flowchart.

选项:

If 24 and 35 are entered as the values for a and b, respectively, then the first nonzero value of T is

If 35 and 27 are entered as the values for a and b, respectively, then after the process b =b/2is completed for the second time, the value of b is

答案:

A B
1答疑

[Problem Solving]

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题目：

The number of defects in the first five cars to come through a new production line are 9, 7, 10, 4, and 6, respectively. If the sixth car through the production line has either 3, 7, or 12 defects, for which of theses values does the mean number of defects per car for the first six cars equal the median?
 
 
I.     3
II.    7
III.   12

选项:

A、I only
B、II only
C、III only
D、I and III only
E、I, II, and III

答案:

D
1答疑

[Data Sufficiency]

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题目：

For each positive integer n , the integeris defined by. What is the value of the positive integer k  ?
(1)   When k  is divided by 4, the remainder is 1.
(2)  

选项:

答案:

B
1答疑

[Critical Reasoning]

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题目：

Maize contains the vitamin niacin, but not in a form the body can absorb. Pellagra is a disease that results from niacin deficiency. When maize was introduced into southern Europe from the Americas in the eighteenth century, it quickly became a dietary staple, and many Europeans who came to subsist primarily on maize developed pellagra. Pellagra was virtually unknown at that time in the Americas, however, even among people who subsisted primarily on maize.

Which of the following, if true, most helps to explain the contrasting incidence of pellagra described above?

选项:

A、Once introduced into southern Europe, maize became popular with landowners because of its high yields relative to other cereal crops.
B、Maize grown in the Americas contained more niacin than maize grown in Europe did.
C、Traditional ways of preparing maize in the Americas convert maize's niacin into a nutritionally useful form.
D、In southern Europe many of the people who consumed maize also ate niacin-rich foods.
E、Before the discovery of pellagra's link with niacin, it was widely believed that the disease was an infection that could be transmitted from person to person.

答案:

C
1答疑

[Data Sufficiency]

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题目：

If n and k are positive integers, is n/k an even integer?
(1)     n is divisible by 8.
(2)     k is divisible by 4.

选项:

答案:

E
1答疑

[Reading Comprehension]

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文章：

A meteor stream is composed of dust particles that have been ejected from a parent comet at a variety of velocities. These particles follow the same orbit as the parent comet, but due to their differing velocities they slowly gain on or fall behind the disintegrating comet until a shroud of dust surrounds the entire cometary orbit. Astronomers have hypothesized that a meteor stream should broaden with time as the dust particles' individual orbits are perturbed by planetary gravitational fields. A recent computer-modeling experiment tested this hypothesis by tracking the influence of planetary gravitation over a projected 5,000-year period on the positions of a group of hypothetical dust particles. In the model, the particles were randomly distributed throughout a computer simulation of the orbit of an actual meteor stream, the Geminid. The researcher found, as expected, that the computer model stream broadened with time. Conventional theories, however, predicted that the distribution of particles would be increasingly dense toward the center of a meteor stream. Surprisingly, the computer model meteor stream gradually came to resemble a thick walled, hollow pipe.

Whenever the Earth passes through a meteor stream, a meteor shower occurs. Moving at a little over 1,500,000 miles per day around its orbit, the Earth would take, on average, just over a day to cross the hollow, computer-model Geminid stream if the stream were 5,000 years old. Two brief periods of peak meteor activity during the shower would be observed, one as the Earth entered the thick-walled "pipe" and one as it exited. There is no reason why the Earth should always pass through the stream's exact center, so the time interval between the two bursts of activity would vary from one year to the next.

Has the predicted twin-peaked activity been observed for the actual yearly Geminid meteor shower? The Geminid data between 1970 and 1979 show just such a bifurcation, a secondary burst of meteor activity being clearly visible at an average of 19 hours(1,200,000 miles)after the first burst. The time intervals between the bursts suggest the actual Geminid stream is about 3000 years old.

题目：

According to the passage, which of the following is an accurate statement concerning meteor streams?

选项:

A、Meteor streams and comets start out with similar orbits, but only those of meteor streams are perturbed by planetary gravitation.Meteor streams grow as dust particles are at traced by the gravitational fields of comets.
B、Meteor streams are composed of dust particles derived from comets.
C、Comets may be composed of several kinds of materials, while meteor streams consist only of large dust particles.
D、Once formed, meteor streams hasten the further disintegration of comets.

答案:

C
1答疑

[Problem Solving]

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题目：

There are 11 women and 9 men in a certain club. If the club is to select a committee of 2 women and 2 men, how many different such committees are possible?

选项:

A、120
B、720
C、1,060
D、1,520
E、1,980

答案:

E
1答疑

[Reading Comprehension]

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文章：

题目：

According to the passage, which of the following describes a result of the way in which researchers generally conduct clinical trials?

选项:

A、They expend resources on the storage of information likely to be irrelevant to the study they are conducting.
B、They sometimes compromise the accuracy of their findings by collecting and analyzing more information than is strictly required for their trials.
C、They avoid the risk of overlooking variables that might affect their findings, even though doing so raises their research costs.
D、Because they attempt to analyze too much information, they overlook facts that could emerge as relevant to their studies.
E、In order to approximate the conditions typical of medical treatment, they base their methods of information collection on those used by hospitals.

答案:

A
1答疑

[Critical Reasoning]

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题目：

A city plans to attract new citizens with new housing and new facilities such as parks, recreation centers, and libraries. One component of the city's plan is to require that developers seeking permission to build this new housing provide these additional facilities at no cost to the city.
Which of the following, if true, would point to a possible flaw in the city's plan?

选项:

A、Developers would pass along their costs to the buyer, thereby raising the cost of housing units beyond the ability of likely purchasers to afford them.
B、Light, nonpolluting industries have located in the area, offering more jobs and better-paying jobs than do the more- established industries in the area. 
C、Other towns and cities nearby have yet to embark on any comparable plans to attract new citizens. 
D、Most developers see the extra expense of providing municipal facilities as simply one of the many costs of doing business. 
E、Studies show that purchasers of new houses, especially first-time buyers, rank recreational resources as an important factor in deciding to buy a particular house.

答案:

A
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1940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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5049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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5728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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1928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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4153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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2914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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1931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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2014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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428560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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435698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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