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1E
Conclusion: if the ban is passed, the Ythex engine ought to sell well in Marania after that time.
E is correct,
Ythex engine is expensive but there is nothing pushing the businesses to switch to this engine. The ban, if enforced, will ultimately mean they have to switch from their current engines. If there is another company that makes inexpensive, more popular and cleaner engines, surely the businesses will switch to that engine.
D is close, but there is no reason to believe that difficulty in enforcing a ban doesn't mean that the ban WILL NOT be enforced at some point.
Consider the logic of the passage: Ythex's main rival is Onez. Onez's product is currently widely used and cheaper than Ythex's new product. However, if the ban is passed, the use of Onez's product will be banned.
The specific logic here is that Ythex's product ought to sell well BECAUSE the ban will eliminate Ythex's main competition. But if other manufacturer's have produced a new product that is JUST AS popular and clean-running as Ythex's product, then Ythex WILL in fact have new competition. If there would be new competition, then we cannot reason that Ythex's product ought to sell well BECAUSE the ban will elimination competition!
In other words, the argument is that Ythex's product ought to sell well when Onez's product goes away. But if other products (regardless of how many) will enter the market when Onez's product goes away, then we have no idea whether competition will increase, decrease, or stay the same. Without (E), we cannot conclude that Ythex's new product ought to sell welll
Looking at Option A
How the number of diesel engines compares to the number of other types of engines does not matter. Maybe diesel engines only represent 10% of the total engines. Regardless, "Ythex's engine is well-suited for use in the thriving warehousing businesses in Marania." We don't care how sales of the new diesel engine compare to sales of other engines.
If the currently used diesel engines are banned and warehousing businesses replace the banned engines with Ythrex's new product, then Ythrex's new product ought to sell well.
2 B
MSR experiments were conducted.
Most animals showed social behaviour such as aggression.
Great apes, on repeated exposure, show self-directed behaviour.
Implication - Great apes have a capacity for self-awareness unique among nonhuman species.
Most animals did not show MSR so we are concluding that they are not self aware. Only great apes showed MSR so we are concluding that only they are self aware.
What is the assumption?
A. Gallup's work has established that the great apes have a capacity for MSR unique among nonhuman species.
We don't know what Gallup's work has established. We are discussing the experiments and their implications.
B. If an animal does not have the capacity for MSR, it does not have the capacity for self-awareness.
Correct. We are assuming that if an animal does not show MSR, it is not self aware. That is why we are implying that self awareness is unique in great apes.
Negate: If an animal does not have the capacity for MSR, it does have the capacity for self-awareness.
Most animals do not show MSR. We are concluding that they do not have capacity for self awareness. If we are given that they have capacity for self awareness, then our conclusion fails.
C. If a researcher exposes an animal to a mirror and that animal exhibits social behavior, that animal is incapable of being self-aware.
Not true. The argument tells us that repeated exposure to mirror leads to MSR in great apes. The first few times, perhaps even great apes exhibit social behaviour. We are not assuming this.
D. When exposed to a mirror, all animals display either social behavior or self-directed behavior.
Not assumed. They could display some other kind of behaviour too. We are only implying about self directed behaviour.
E. Animals that do not exhibit MSR may demonstrate a capacity for self-awareness in other ways.
Not assumed. In fact, the argument assumes opposite of this.
Answer (B)
3C
Premises:
Sea otter population declined - but no sign of disease and malnutrition so predators might have been responsible.
Seal population declined dramatically.
Orcas eat otters when seals are not available.
Conclusion:
Orcas must have led to otter population decline.
We need to strengthen that orcas are responsible for the huge decline in otter population.
C. Most of the surviving sea otters live in a bay that is inaccessible to orcas.
Had the option said, "Most sea otters live in a bay that is inaccessible to orcas," then the option would have weakened our argument.
But the option says, "Most of the surviving sea otters live in a bay that is inaccessible to orcas." This means that the otters that are left are the ones where orcas cannot reach. Wherever orcas can reach, otters have disappeared from there. It means that it is highly probable that orcas have been binging on otters wherever possible.
Imagine a meadow which was full of grass 2 months back. A small part of the meadow is fenced. Some cattle was introduced in the meadow two months back. What happens if after to months you see that most of the grass is gone except the small part which was fenced? The likely reason is that the cattle ate the grass and hence reduced it.
This is the same concept.
None of the other options are relevant.
A The population of sea urchins, the main food of sea otters, has increased since the sea otter population declined.
Irrelevant
B. Seals do not eat sea otters, nor do they compete with sea otters for food.
What seals eat is none of concern. What we need to strengthen is that orcas ate up the otters.
D. The population of orcas in the Aleutian Islands has declined since the 1980s.
This doesn't strengthen that orcas ate the otters. Perhaps some orcas couldn't adapt to decrease in seal population. We don't know.
E An increase in commercial fishing near the Aleutian Islands in the 1980s caused a slight decline in the population of the fish that seals use for food.
This might affect seal population. It doesn't strengthen that orcas ate otters.
Answer (C)
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4D
tart with the scientists' hypothesis. We are told that mice infected with a herpesvirus generally develop keratitis. The hypothesis is that "these cases of keratitis (those in mice infected with herpesvirus) are caused by antibodies to herpesvirus".
Now that we've identified the hypothesis, let's look at how the scientists arrived at this hypothesis:
- When mice are infected by a virus, their immune systems produce antibodies to fight the infection.
- These antibodies are supposed to destroy the virus by binding to proteins on its surface.
- So if a mouse is infected with herpesvirus, we would expect the mouse's immune system to produce antibodies that would bind to proteins on the virus's surface. Great!
- Unfortunately, mice with herpesvirus generally develop keratitis, a degenerative disease affecting part of the eye. Interesting... why does that happen?
- Well, proteins on the surface of cells in this part of the eye closely resemble those on the herpesvirus surface. Uh oh... maybe the antibodies that are supposed to bind to the herpesvirus proteins are ALSO binding to proteins in the eye, since those proteins closely resemble those of the virus.
- So the antibodies are supposed to be attacking the virus, but, if the hypothesis is correct, then those antibodies are also attacking cells in the eye.
This hypothesis seems to make sense, but we need an answer choice that gives it the greatest additional support:
In order for this statement to support the hypothesis, we would need additional information. What happens when mice are infected with those other types of virus? Do the organs with similar proteins suffer any damage? If so, then the hypothesis would be supported. But without further evidence, choice (A) doesn't help. Eliminate (A).
These poor mice won't be able to fight the herpesvirus. If these mice also did NOT develop keratitis once infected with the herpesvirus, then we would have some solid support for the hypothesis. Unfortunately, we are not given such information.
All we know is that the mice who can't fight the herpesvirus contract the virus at about the same rate as other mice. We aren't interested in herpesvirus contraction rates. We are interested in the cause of the keratitis that generally develops in the infected mice. Eliminate (B).
This statement probably weakens the hypothesis. The scientists argue that the keratitis is caused by the antibodies. If these mice produce the same levels of antibodies and the antibodies cause the keratitis, then why wouldn't those mice also develop keratitis? This suggests that the antibodies aren't actually causing the keratitis.
If infected mice that do not develop keratitis did NOT produce as many antibodies as infected mice that do develop keratitis, then we would have support for the hypothesis. But this is not what statement (C) says, so eliminate (C).
Ah ha! This is what we were looking for in choice (B). The mice are unable to form antibodies in response to herpes infections. These poor mice cannot fight the virus, but they also do not develop keratitis. No antibodies, no keratitis. This certainly supports the scientists' hypothesis, so hang on to (D).
Notice that the hypothesis specifically refers to "THESE CASES of keratitis." Which cases? Those that develop in mice infected with herpesvirus. So the scientists are not trying to explain causes of ALL cases of keratitis. Instead, they are only trying to explain the cases that develop in mice infected with herpesvirus.
Choice (E) does suggest that there are other ways to develop keratitis (besides the way proposed by the scientists). If anything, this slightly weakens the hypothesis by implying that something else (besides the antibodies to herpesvirus) could be causing these cases of keratitis. At best, choice (E) is irrelevant. At worst, it weakens the hypothesis, so eliminate (E).
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5B
The heart of Sharon's argument is pretty straightforward: she thinks that what Roland sees is somewhat "normal", and not "alarming".
Let’s break down the reasoning behind her argument:
- 1. A "normal" unemployment rate is 1/20.
2. So if you know 20 typical workers, odds are good that one will be unemployed.
3. And then if you know 50 workers, at least 1 of them will probably be unemployed.
4. Therefore, it’s likely at any given time that 90% of people in the country know at least 1 unemployed person.
In her reasoning, Sharon refers to nationwide levels of unemployment. When she jumps to step 4 of her argument, she assumes that the employment patterns of the 50 workers each of us knows personally will resemble the nationwide employment patterns. In order to accept this assumption, we need evidence that the normal unemployment rate in any given area will roughly match the normal rate of unemployment for the entire country. Otherwise, it could be the case that the unemployed workers are overwhelmingly concentrated in a few parts of the country, and most people elsewhere might NOT know any unemployed workers.
So Sharon's argument relies on which of these assumptions?
Quote:
It makes no difference whether normal levels of unemployment are exceeded rarely or frequently. As long as the current level of unemployment is normal, then Sharon’s argument is valid.
In other words, normal levels of unemployment could be exceeded frequently. But according to Sharon, the data cited by Roland is evidence that unemployment levels are normal right now. Sharon’s argument does not rely on choice (A), so eliminate this one.
Quote:
Choice (B) gets to the heart of Sharon’s assumption. If unemployment is evenly distributed across the population as opposed to being concentrated in certain states, cities and industries, then we’ll have an easier time agreeing with Sharon. If (B) is true, then any person who knows approximately 50 workers -- anywhere in the country -- is likely to know at least one unemployed worker, even if unemployment levels are moderate.
If (B) were NOT true and unemployment levels were moderate, then we would expect people in the geographically isolated segments to know several unemployed workers. In that case, most people in other parts of the country would NOT likely know at least one unemployed worker. If (B) were not true, then Roland’s evidence would be "alarming", and Sharon’s argument would fall apart.
Let’s keep choice (B) for now and try to eliminate the rest.
Quote:
Choice (C) could certainly weaken Roland’s argument (by suggesting that the evidence is normal, not alarming). But does Sharon’s argument rely on this assumption? What if unemployment levels are sometimes LESS than moderate? In that case, there would certainly be times when the number of people who each know someone who is unemployed is NOT higher than 90% of the population.
Regardless, we are only interested in the fact that that 90 percent NOW report that they know someone who is unemployed. According to Sharon, this is no cause for alarm. Sharon’s argument would be the same regardless of whether (C) is true, so we can eliminate this one.
Quote:
Sharon’s argument doesn’t depend on whether Roland is honest. There would be no reason for continuing to this conversation if Roland were rattling off fake news he saw on Facebook, but Sharon’s logical connection wouldn’t be affected.
Sharon’s argument is basically, “Even if your evidence is true, there is no cause for alarm.” If the evidence is false, Roland might be a liar, but Sharon’s logic remains sound.
(D) isn't necessary, so we can eliminate it.
Quote:
Choice (E) very well may be true, but it tells us nothing that would affect the logical argument Sharon is making. She says we shouldn’t be alarmed because normal unemployment rates explain the seemingly abnormal rates of knowing an unemployed person. Fear of losing one's job is completely irrelevant to her argument.
So (E) is out, and (B) is our answer.
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6C
Evidence: Study showing people who own computers less television than people who do not own computers.
Conclusion: Television viewing has declined due to computers.
Question has been asked to weaken the argument.
(A) many people who watch little or no television do not own a computer. -Irrelevant, since we are concerned about comparison between TV and computer, rather then between TV and non-computer.
(B) even though most computer owners in the United States watch significantly less television than the national average, some computer owners watch far more television than the national average. -Irrelevant, its just talking about some computer owners watching TV.
(C) computer owners in the United States predominately belong to a demographic group that have long been known to spend less time watching television than the population as a whole does. -Correct, weakens the argument by directly challenging the conclusion, even though the survey result is correct as the survey is giving average results.
(D) many computer owners in the United States have enough leisure time that spending significant amounts of time on the computer still leaves ample time for watching television. -Irrelevant, we are just concerned about comparing two different group of people, i.e computer owners and non-computer owners. Doesn't matter if computer owners are spending lot of time on TV, but we don't know if non-computer owners are spending even more time
(E) many people use their computers primarily for tasks such as correspondence that can be done more rapidly on the computer, and doing so leaves more leisure time for watching television. -Same error, as in D
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7A
The government wants to increase the amount of money available for development loans for businesses. How does the government plan to do that?
- The government plans to modify the income-tax structure.
- The modifications are supposed to induce individual taxpayers to put a larger portion of their incomes into retirement savings accounts.
- As more money is deposited into retirement savings accounts, more money becomes available to borrowers.
The government hopes that increasing the money available to borrowers will increase the amount of money available for development loans for business, but is that necessarily the case? We need to select the answer choice that raises the most serious doubt regarding the effectiveness of the government's plan.
Quote:
The government wants to modify the income-tax structure to make people put more of their income into retirement savings accounts. This should increase the amount of money available to borrowers. But will that money go to development loans for business? What if that money goes to other kinds of loans?
Choice (A) tells us that consumer borrowing WILL increase if personal retirement savings increases. So more money will become available for borrowing, but consumers will borrow some or all of that money. That leaves less (if any) money for development loans. It's possible that some of that money will be used for development loans and that the government's plan will still succeed, but choice (A) raises a serious doubt. Hang on to this one.
Quote:
Choice (B) tells us that the government will suffer a net loss in revenue as a result of this plan. But we are not trying to determine how the plan will impact the government's revenue. We are simply trying to determine whether the plan will succeed in increasing the amount of money available for development loans for businesses. Choice (B) is irrelevant and can be eliminated.
Quote:
It's okay if SOME people chose not to increase their levels of retirement savings. As long as some people DO increase their levels of retirement savings, the government's plan could still work. In other words, we don't need ALL people to increase their savings, only some. Choice (C) does not raise serious doubt and can be eliminated.
Quote:
This is obviously a problem for those businesses whose prospective earnings are insufficient to meet their loan repayment schedules. But we are not concerned with that situation. We simply want to know whether the modifications to the income-tax structure will increase the amount of money available for development loans for business. As long as the amount available for such loans increases, the government's plan will be a success, regardless of whether some businesses can't access that money because they've had problems paying off their loans. Eliminate (D).
Quote:
A possible misunderstanding of choice (E) is to conclude that taxpayers will get the same tax savings regardless of how much they deposit in retirement savings accounts. That might give people less incentive to increase their retirement savings (i.e. "Why should I put more into my retirement savings if it won't increase by tax savings?") and thus jeopardize the government's plan.
But this is not what choice (E) says. Rather, it says that taxpayers will, regardless of their incomes, get "the same tax savings for a given increase in their retirement savings." In other words, if two taxpayers have different incomes but make identical increases in their retirement savings, then both would get the same tax savings. Thus, choice (E) does not affect the government's plan to induce individual taxpayers to put a larger portion of their incomes into retirement savings accounts. Eliminate (E).
Choice (A) is the best answer.
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8 C
Sunlight is free. Infra needed to convert it to electricity is expensive. Say for every one unit of electricity, you need to spend $50 in a solar power plant (this $50 is the infra cost for solar power).
Oil is expensive. Infra needed to convert it to electricity, not so much. Say for every one unit of electricity, you need to spend $40 in an oil fired power plant. Say, the split here is $25 + $15 ($25 is the cost of oil used and $15 is cost of infra for a unit of electricity here).
Oil based electricity is cheaper. But if the cost of oil rises by $10 (from $25 to $35), solar power will become viable. Now, at both places, cost of one unit of electricity will be $50.
This $35 = the threshold of economic viability for solar power = the price per barrel to which oil would have to rise (mind you, this isn't the actual price of oil)
What happens if you need to spend only $45 in a solar power plant for a unit of electricity? Would you expect 'the threshold of economic viability for solar power' to go to 30? Yes! Now, for solar viability, 'cost of oil + cost of infra in oil power plant' should be only $45. 'Cost of infra in oil power plant' = 15 so we need the oil to go up to $30 only. That will make solar power plants viable. So the threshold of economic viability should decrease.
But the threshold of economic viability for solar power is still $35! It doesn't decrease. That is the paradox! How do you resolve it? By saying that 'Cost of infra in oil power plant' has also gone down by $5 and is only $10 now.
This is what the scene is like now:
Sunlight is free. Infra needed to convert it to electricity is expensive. For every one unit of electricity, you need to spend $45 in a solar power plant.
Oil is expensive. Infra needed to convert it to electricity, not so much. For every one unit of electricity, you need to spend $35 in an oil fired power plant. The split now is $25 + $10 ($25 is the cost of oil used and $10 is cost of infra for a unit of electricity).
You still need the oil price to go up to $35 so that cost of electricity generation in oil power plant is also $45. So you explained the paradox by saying that "Technological changes have increased the efficiency of oil-fired power plants." So, option (C) is correct.
If you think about it now, the actual price of the oil has nothing to do with 'the threshold of economic viability for solar power'. This threshold is $35 so you need the oil to go up to $35. Whether the actual price of oil is $10 or $15 or $20, it doesn't matter. It still needs to go up to $35 for solar viability. So option (A) is incorrect.
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9 B
HE REORGANISATION CAUSED THE INCREASE IN ADVERTISING SALES....... WE NEED TO CHECK IF THERE COULD HAVE BEEN AN ALTERNATE CAUSE FOT THE SAME?
WHAT IF MORE PEOPLE NOW READ THE Greenvile Times THAN BEFORE AND HENCE THE ADVERTISING SALES HAS INCREASED........
HERE "B" AND " D" ARE CONTENDERS......
(B) Has the circulation of the Greenvile Times increased substantially in the last two years? YES/ NO TO THIS QUESTION WILL DECIDE IF THE NEW REORGANIZATION WAS THE CAUSE FOR INCREASED SALES OR NOT.... CORRECT..
(D) Do any clients of the sales representatives of the Greenvile Times have a standing order with the Times for a fixed amount of advertising per month?.....IF FIXED AMOUNT OF ADVERTISING HAS ALREADY BEEN STIPULATED, HOW COULD THE SALES INCREASE ? IF IT SAID THAT THE CLIENTILE BASE INCREASED WITH FIXED AMOUNT OF STANDING ORDERS, THEN IT COULD HAVE BEEN CORRECT...... HENCE INCORRECT..
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10 A
The argument is that the new system will make customers prefer regular '2-day delivery' to premium 'next-day delivery' because the regular delivery takes one day anyways. They want to solve this by making sure regular delivery does not take one day. The main assumption of this argument is that people pick their service because of the one-day timeline, and not because of other reasons. A weaker assumption is that causing a delay in supply will not affect sales (this requires that potential customers know about the delay). As we know what to look for, we can look for it without pausing to think about each individual answer. This is a Precise approach.
Going over the options, (A) is exactly what we expect and is our answer.
Source : gmatclub.com
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