December 31st, 2009 | 
Author: Pam and Ed are in a line to purchase tickets. How many people are in the line?
(1) There are 20 people behind Pam and 20 people in front of Ed.
(2) There are 5 people between Pam and Ed.
Highlight to see answer: E
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Posted in Data Sufficiency | 
Tags: Data Sufficiency, gmat, gmat review, practice problems | 
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Desertification, the creation of desert-like conditions where none had existed before, is the result of the vagaries of weather and climate or the mismanagement of the land or, in most cases, some combination of both. Such ecological deterioration in the Sahel has been linked in several ways to the increased size of livestock herds. During the fifteen years preceding 1968, a period of extremely favorable rainfall, the pastoralists moved into the marginal regions in the north with relatively large herds. However, with the onset of a series of dry years beginning at the end of the rainy season in 1967, the pastoral populations found themselves overtaxing very marginal rangelands, with the result that the nomads viewed themselves as victims of a natural disaster. The mistaken idea that drought is an unexpected event has often been used to excuse the fact that long-range planning has failed to take rainfall variability into account. People blame the climate for agricultural failures in semiarid regions and make it a scapegoat for faulty population and agricultural policies.
Deterioration and ultimately desertification in the Sahel and in other ecosystems can be combated only if an ecologically realistic carrying capacity for the rangelands is determined. Although there appears to be widespread agreement that such a determination would be significant, there has been little agreement on how to make operational the concept of carrying capacity, defined as the amount of grazing stock that the pasture can support without deterioration of either the pasture or the stock. Should the carrying capacity be geared to the best, the average, or the poorest years? Which combination of statistical measures would be most meaningful for the planning of long-term development of rangelands? On which variables should such an assessment be based, vegetation, rainfall, soil, ground and surface water, or managerial capabilities? Such inconclusiveness within the scientific community, while understandable, creates confusion for the land managers, who often decide to take no action or who decide that all
scientific suggestions are of equal weight and, therefore, indiscriminately choose any one of those suggested. Given the downward spiral of land deterioration, it becomes essential that an ecologically acceptable carrying capacity be established and enforced.
It will also be crucial that land managers know what statistical and quasi-statistical measures actually mean: no single number can adequately describe the climate regime of an arid or semiarid region. Land managers must supplement such terms as the “mean” with more informative statistical measures to characterize adequately the variability of the climate. The understanding of this high degree of variability will serve to remove one of the major obstacles to resolving the perennial problems of the Sahel and of other arid or semiarid regions.
1. The author is primarily concerned with
(A) criticizing a social attitude
(B) suggesting an approach to solving a problem
(C) explaining the mechanics of a process
(D) defending the theories of ecological scientists
(E) establishing criteria for an experiment
2. According to the passage, which of the following contributed to the desertification of the Sahel?
I. The size of the livestock herds grazing on the land
II. The quality of the land in the Sahel
III. The amount of rainfall after 1967
(A) I only
(B) II only
(C) III only
(D) I and III only
(E) I, II, and III
3. It can be inferred from the passage that the nomadic tribes who moved into the marginal regions of the Sahel did NOT
(A) enlarge the size of their livestock herds
(B) conserve water after the drought began
(C) live in the Sahel after 1968
(D) expect a drastic change in weather conditions
(E) seek governmental aid in overcoming drought conditions
4. It can be inferred from the passage that the concept of the carrying capacity of land is
(A) still hypothetical rather than practical
(B) basically political rather than ecological
(C) independent of climatic conditions
(D) relatively unknown among ecologists
(E) generally misrepresented by ecologists
5. Which of the following best states the author’s view concerning the relationship between the ecological scientist and the land manager?
(A) The scientist has not provided the manager with clear guidelines that can be used in regulating the productivity of land.
(B) The scientist has provided theories that are too detailed for the manager to use successfully.
(C) The scientist and the manager, in attempting to regulate the use of semiarid land, have ignored the traditional behavior patterns of pastoral communities.
(D) The manager has misunderstood and hence misapplied the suggestions of the scientist.
(E) The manager has chosen from among the scientist’s suggestions those that are economically rather than ecologically safe.
6. With which of the following statements concerning desertification would the author be most likely to agree?
(A) It is the result of factors beyond the control of science.
(B) It is a problem largely affecting arid regions.
(C) It could be prevented if land managers understood statistics.
(D) It is not always the result of drastic climate changes alone.
(E) It is not attributable to faulty agricultural policies.
7. According to the passage, a statistical description of the climate regime of an arid or semiarid region would probably be
(A) misleading
(B) impossible
(C) complex
(D) meaningless
(E) abstract
8. The tone of the passage can best be described as
(A) flippant
(B) objective
(C) aggressive
(D) apologetic
(E) unconcerned
Highlight to see answers: 1. B 2. D 3. D 4. A 5. A 6. D 7. C 8. B
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Posted in Reading Comprehension |
Tags: gmat, gmat review, practice problems, Reading Comprehension |
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The peculiar evil of silencing the expression of an opinion is that it robs the human race. It takes from posterity, as well as the existing generation, and from those who dissent from the opinion even more than from those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth; if it is wrong, they lose what is almost as great a benefit: the clearer perception and livelier impression of truth, produced by its collision with error.
Which one of the following best expresses the conclusion presented in the argument?
(A) Silencing the expression of an opinion is robbing the human race.
(B) Silencing the expression of an opinion harms those who dissent more than those who agree.
(C) Anyone who agrees with an opinion would not want to silence its expression.
(D) Gaining a clearer perception and livelier impression of truth is a great benefit.
(E) The greatest benefit is the opportunity of exchanging truth for error.
Highlight to see answer: A
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Posted in Critical Reasoning |
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Most Corporations pay at least twice as much to full-time employees, if the value of benefits, sick days, and paid vacation days are included in earnings, than to part-time employees, whose hourly wages are often higher than those of their full-time colleagues.
(A) are included in earnings, than
(B) are included in earnings, as
(C) is included in earnings, than they pay
(D) is included in earnings, as is paid
(E) is included in earnings, as they pay
Highlight to see answer: E
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Posted in Sentence Correction |
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If 10 persons meet at a reunion and each person shakes hands exactly once with each of the others, what is the total number of handshakes?
(A) 10•9•8•7•6•5•4•3•2•1
(B) 10•10
(C) 10•9
(D) 45
(E) 36
Highlight to see answer: D
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Posted in Problem Solving |
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