Erin: Scientists also blame PAHs for 10,000 premature deaths in this country each year from lung and heart disease. So the proposed regulations would save thousands of lives.
Summarize Argument
Erin concludes that the proposed regulation decreasing PAH emissions from automobile exhaust would save thousands of lives. This is because scientists blame PAHs for many premature deaths from lung and heart disease.
Notable Assumptions
Erin assumes that the same problem Albert notes in his argument—that no causal link between PAHs and cancer have been proven—isn’t relevant to the diseases she mentions. This means she either thinks that there is a causal link between PAHs and lung and heart disease, or that it’s unimportant to establish such a link when scientists blame several major health problems on PAHs.
A
Most automobile manufacturers are strongly opposed to additional automobile emissions regulations.
We can imagine automobile manufacturers don’t like regulations. But we’re not interested in what they like or don’t like. We need to know about the link between PAHs from automobile emissions and various diseases.
B
It is not known whether PAHs are a causal factor in any diseases other than heart and lung disease and cancer.
We don’t know if PAHs are a causal factor in heart and lung disease and cancer. This just tells us that other diseases fall into the same “unknown” category.
C
Even if no new automobile emissions regulations are enacted, the amount of PAHs released into the atmosphere will decrease if automobile usage declines.
There would still be a benefit to regulating PAHs further, given their link to diseases. Thus, this doesn’t weaken the notion that PAHs should be regulated.
D
Most of the PAHs released into the atmosphere are the result of wear and tear on automobile tires.
Even if PAHs from automobile exhaust were banned, the majority of current PAH production would continue through wear and tear on automobile tires. Thus, the regulation wouldn’t in fact save “thousands of lives.”
E
PAHs are one of several components of automobile exhaust that scientists suspect of causing cancer.
This doesn’t tell us that PAHs constitute only a small or insignificant fraction of the carcinogenic effects of automobile exhaust, so we can’t assume Erin would be wrong about the regulation. Banning PAHs may still save thousands of lives.
Summarize Argument: Phenomenon-Hypothesis
The author explains a phenomenon and supports that explanation. The unusual sparseness of Australia’s ecosystems explains why the continent has fewer species of carnivorous mammals but as many species of carnivorous reptiles. Carnivorous mammals are at a disadvantage in an ecosystem with little food because they need to eat much more than carnivorous reptiles do.
Identify Conclusion
The conclusion is an explanation for the carnivorous species imbalance: “This is probably a consequence of the unusual sparseness of Australia's ecosystems.”
A
Australia has considerably fewer species of carnivorous mammals than any other continent does but about as many carnivorous reptile species as other continents do.
This is a phenomenon that the argument attempts to explain. It is context that sets up the claim.
B
In ecosystems in which there is relatively little food carnivorous mammals are at a disadvantage relative to carnivorous reptiles.
This is support for why Australia’s sparse ecosystem explains the phenomenon.
C
The unusual sparseness of Australia’s ecosystems is probably the reason Australia has considerably fewer carnivorous mammal species than other continents do but about as many carnivorous reptile species.
This restates the author’s ultimate argument - the sparse ecosystem explains the species imbalance.
D
The reason that carnivorous mammals are at a disadvantage in ecosystems in which there is relatively little food is that they must eat much more in order to survive than carnivorous reptiles need to.
This is support for why Australia’s sparse ecosystem explains the phenomenon.
E
Because Australia’s ecosystems are unusually sparse, carnivorous mammals there are at a disadvantage relative to carnivorous reptiles.
The argument is not only saying that sparseness contributes to a disadvantage, but that the disadvantage then explains the difference in the number of species. This is a major premise, but not the ultimate conclusion.
Linguist: The Sapir-Whorf hypothesis states that a society’s world view is influenced by the language or languages its members speak. But this hypothesis does not have the verifiability of hypotheses of physical science, since it is not clear that the hypothesis could be tested.
Summary
According to the Sapir-Whorf hypothesis, how a society thinks about the world is influenced by the language that society speaks. However, it is not clear that this hypothesis could be tested. Therefore, the Sapir-Whorf hypothesis does not have a similar verifiability compared to the hypotheses of physical science.
Strongly Supported Conclusions
It is unclear whether the Sapir-Whorf hypothesis is true or false.
A
The Sapir-Whorf hypothesis is probably false.
This answer is unsupported. It is too strong to say the hypothesis is “probably false.” We only know from the stimulus that the hypothesis cannot be verified. An absence of verification does not necessarily mean that something is false.
B
Only the hypotheses of physical science are verifiable.
This answer is unsupported. Physical sciences were given as an example of types of hypotheses that are verifiable. It is too strong to say that only these hypotheses are verifiable.
C
Only verifiable hypotheses should be seriously considered.
This answer is unsupported. The Linguist never discusses what types of hypotheses should be seriously considered.
D
We do not know whether the Sapir-Whorf hypothesis is true or false.
This answer is strongly supported. Since we know the Sapir-Whorf hypothesis is not able to be verified, then we cannot know whether it is true or false.
E
Only the hypotheses of physical science should be taken seriously.
This answer is unsupported. The Linguist never discusses what types of hypotheses should be taken seriously.
"Surprising" Phenomenon
Erosion wears down mountains, yet the tallest mountains are found in the areas with the greatest erosive forces.
Objective
We’re looking for a hypothesis that explains why the highest mountain ranges are found in areas with prevalent erosive forces, which presumably lessen how high mountains are. The correct hypothesis would explain not only why these opposing phenomena can co-exist, but why they’re frequently seen together.
A
Patterns of extreme wind and precipitation often result from the dramatic differences in elevation commonly found in the highest mountain ranges.
Extreme erosive forces stem from the presence of high mountain ranges. No wonder, then, that the highest mountain ranges experience prevalent erosive forces!
B
The highest mountain ranges have less erosion-reducing vegetation near their peaks than do other mountain ranges.
This doesn’t explain anything about erosive forces themselves. Maybe the vegetation that shields other mountains from erosion isn’t present among the highest mountain ranges, but why are the erosive forces so prevalent to begin with?
C
Some lower mountain ranges are formed by a different collision process, whereby one tectonic plate simply slides beneath another of lesser density.
This doesn’t explain anything about why erosive forces are more prevalent among the highest mountain ranges than other ranges. We don’t really care how mountains are made.
D
The amount of precipitation that a given region of the earth receives may vary considerably over the lifetime of an average mountain range.
We need to know why the highest mountain ranges are found in the areas with prevalent erosive forces. The fact that precipitation can vary in a region doesn’t help us reconcile this surprising fact.
E
The thickening of the earth’s crust associated with the formation of the highest mountain ranges tends to cause the thickened portion of the crust to sink over time.
That may be true, but why are the highest mountain ranges found in areas with very prevalent erosive forces? This doesn’t clear up our stimulus.
Summarize Argument
Singletary says the ordinance requiring helmets is more concerned with the appearance of bicycle safety than actual safety. Why? If they were actually concerned about safety they would make more bicycle lanes and educate drivers, not mandate helmets.
Identify Argument Part
This is an action Singletary says the city would do if it actually cared about safety more than appearing to be safe. Since the city didn’t do it, they don’t actually care more.
A
It is cited as evidence for the claim that the city misunderstands the steps necessary for ensuring bicyclists’ safety.
The argument does not claim the city misunderstands, it claims the city is not concerned with actual safety.
B
It is used as partial support for a claim about the motivation of the city.
This claim acts as partial support because it shows what the city would do, but didn’t, if it actually cared about safety.
C
It is offered as evidence of the total ineffectiveness of the helmet ordinance.
Singletary does not claim the helmet measure is ineffective. He claims that it shows the city doesn’t truly care about safety, effective or not.
D
It is offered as an example of further measures the city will take to ensure bicyclists’ safety.
There is no evidence that the city will implement this in the future. Singletary only presents it as something that would have happened if the city cared about safety.
E
It is presented as an illustration of the city’s overriding interest in its public image.
The conclusion is not that the city has an overriding interest in its public image. The conclusion is that the city prioritized the appearance of safety over actual safety. While this may be true, it is an inaccurate depiction of what the statement is supporting.