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1.
Loggerhead turtles live and breed in distinct groups, of which some are in the Pacific Ocean and some are in the Atlantic. New evidence suggests that juvenile Pacific loggerheads that feed near the Baja Peninsula hatch in Japanese waters 10,000 kilometers away. Ninety-five percent of the DNA samples taken from the Baja turtles match those taken from turtles at the Japanese nesting sites.
The argument seems to demonstrate that since the DNA samples match highly between the Baja turtles and the Japanese turtles, the turtles that come from the Japanese nesting sites are those turtles that feed near the Baja Peninsula. Which one of the following, if true, most seriously weakens the reasoning above?
(A) Nesting sites of loggerhead turtles have been found the Pacific coast of North America Several thousand kilometers north of the Baja peninsula.
Even though nesting sites have been found the Pacific coast, we cannot prove that the relationship between the Baja turtles and the turtles from the Pacific coast nesting sites. (B) The distance between nesting sites and feeding sites of Atlantic loggerhead turtles is less than 5,000 kilometers.
The choice is only referred to Atlantic turtles, rather than Baja turtles or turtles from Japanese nesting sites. (C) Loggerhead hatchlings in Japanese waters have been declining in number for the last decade while the number of nesting sites near the Baja peninsula has remained constant.
Although we can see the differences, there is no evidence supported to weaken the argument.
Even though the number of hatchlings is declined, the number of nesting sites would remain constant, albeit with fewer turtles at each. Because of this possibility, the answer does not undermine the argument. (D) Ninety-five percent of the DNA samples taken from the Baja turtles match those taken from Atlantic loggerhead turtles.
Since the similarity situation happens between Baja turtles and Atlantic turtles, the choice can weaken the argument. We should know that Japan is in the Pacific Ocean. BA (E) Commercial aquariums have been successfully breeding Atlantic loggerheads with Pacific loggerheads for the last five years.
From this choice, we know nothing about the Baja turtles.
25. (30261-!-item-!-188;#058&004144) Twelve years ago and again five years ago, there were extended periods when the Darfir Republic's currency, the pundra, was weak: its value was unusually low relative to the world's most stable currencies. Both times a weak pundra made Darfir's manufactured products a bargain on world markets, and Darfir's exports were up substantially. Now some politicians are saying that, in order to cause another similarly sized increase in exports, the government should allow the pundra to become weak again.
The argument seems to involve in the line of reasoning that in the future, the situation will remain unchanged just as it did in the history. However, it is very possible that the trend will change or even reverse, severely weakening the argument. Admittedly, the argument would be even weaker each day as time goes by. Which of the following, if true, provides the government with the strongest grounds to doubt that the politicians' recommendation, if followed, will achieve its aim?
(A) Several of the politicians now recommending that the pundra be allowed to become weak made that same recommendation before each of the last two periods of currency weakness.
What these politicians recommended before has nothing to do with the current situation. (B) After several decades of operating well below peak capacity, Darfir's manufacturing sector is now operating at near-peak levels.
Since the current condition of Darfir’s manufacturing sector is changed, the fact severely weakens the argument. BA (C) The economy of a country experiencing a rise in exports will become healthier only if the country's currency is strong or the rise in exports is significant.
Shell Game: the argument talks about the rise in exports, rather than the health of the economy of a country. (D) Those countries whose manufactured products compete with Darfir's on the world market all currently have stable currencies.
Even though it reveals that other countries’ situation, we do not know what will happen to Darfir. (E) A sharp improvement in the efficiency of Darfir's manufacturing plants would make Darfir's products a bargain on world markets even without any weakening of the pundra relative to other currencies.
The choice seems very attractive at first glance, but the argument talks about these politicians’ recommendation that the country makes the pundra weak again, rather than without any weakening of the pundra relative to other currencies.
26. (31045-!-item-!-188;#058&004365) The population of Megacity, a sprawling metropolis in Remsland, has grown at a fairly steady rate for over a century. A hundred years ago, poor sanitation in the city caused high mortality rates among the city's inhabitants, and what fueled the population increase was immigration from rural villages. This immigration has continued and even increased. Moreover, in recent decades, city sanitation has improved enormously. Yet the city's population growth has not significantly accelerated. Which of the following, if true, most helps to explain why the city's population growth rate has not changed?
(A) Mortality rates that were associated with poor sanitation in Megacity a hundred years ago were orders of magnitude higher than are mortality rates associated with vehicular traffic, which is currently a major cause of death in the city.
The choice seems valid at first glance, but a more thorough analysis reveals that it is highly questionable. Because mortality rates caused by poor sanitation are higher than mortality rates caused by vehicular traffic, we should think about the now condition of population of Megacity would significantly accelerate. (B) For several decades, Megacity, as distinct from the countryside, has had a steadily declining birth rate.
By introducing the decline in the birth rate, the choice successfully reconciles the contradiction. BA (C) Cities smaller than Megacity have also experienced sustained population growth.
There is no relationship with the cities smaller than Megacity. (D) The great majority of immigrants to Remsland settle in Megacity, at least initially.
Actually, the choice stimulates the contradiction. (E) Megacity has long offered better employment prospects than most rural areas.
The same to D.
27. (31231-!-item-!-188;#058&004411) Plant scientists have used genetic engineering on seeds to produce crop plants that are highly resistant to insect damage. Unfortunately, the seeds themselves are quite expensive, and the plants require more fertilizer and water to grow well than normal ones. Thus, for most farmers the savings on pesticides would not compensate for the higher seed costs and the cost of additional fertilizer. However, since consumer demand for grains, fruits, and vegetables grown without the use of pesticides continues to rise, the use of genetically engineered seeds of this kind is likely to become widespread. In the argument given, the two portions in boldface play which of the following roles?
(A) The first supplies a context for the argument; the second is the argument's main conclusion.
The second is the main conclusion. Actually, the first is contradictory to the second. (B) The first introduces a development that the argument predicts will have a certain outcome; the second is a state of affairs that the argument denies will be part of that outcome. (C) The first presents a development that the argument predicts will have a certain outcome; the second acknowledges a consideration that weighs against that prediction.
The second is a prediction that weighs against the prediction drawn from the first. BA (D) The first provides evidence to support a prediction that the argument seeks to defend; the second is that prediction. (E) The first and the second each provide evidence to support the argument's main conclusion.
28. (31510-!-item-!-188;#058&004526) First-time computer buyers buying PXC home computers typically buy models that cost much less and have a smaller profit margin per computer than do PXC computers bought by people replacing their computers with more powerful models. Last year PXC's profits from computer sales were substantially higher than the previous year, although about the same number of PXC computers were sold and the prices and profit margins for each computer model that PXC sells remained unchanged. If the statements above are true, which of the following is most strongly supported by them?
(A) PXC's competitors raised the prices on their computers last year, making PXC computers more attractive to first-time computer buyers.
The argument has showed that the same number of PXC computers was sold and the prices and profit margins for each computer model remained unchanged. (B) The number of people buying PXC computers who also bought PXC computer-related products, such as printers, was larger last year than the previous year.
Although the choice seems valid at first glance, the argument talks nothing about PXC computer-related products, such as printers. (C) Among computer buyers who bought a PXC computer to replace their existing computer, the proportion of buyers who were replacing a computer made by a competitor of PXC was greater last year than the previous year.
Actually, the choice weakens the argument. If PXC computer buyers replaced computers made by a competitor of PXC, the profit of PXC would decrease. (D) The proportion of PXC computers bought by first-time computer buyers was smaller last year than the previous year.
Since the proportion of PXC computers bought by first-time computer buyers was smaller, the proportion of PXC computers bought by people replacing their computers with more powerful models was greater last year than the previous year. Please notice that the argument only talks about two kinds of buyers of PXC computers.BA (E) PXC's production costs for its computers were lower last year than they had been the previous year.
The same to A.
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