Baumgartner’s comparison of the environmental hazards of gasoline-powered cars with those of electric cars is misleading. He examines only production of the cars, whereas it is the product’s total life cycle—production, use, and recycling—that matters in determining its environmental impact. A typical gasoline-powered car consumes 3 times more resources and produces 15 to 20 times more air pollution than a typical electric car.

Summarize Argument: Counter-Position
The argument concludes that Baumgartner’s methods of comparing electric cars with gasoline-powered cars is misleading. This is because an effective comparison should consider the entire life cycle of the car. Baumgartner’s comparison only considers production, so it will not be an accurate evaluation of the relative environmental impact of each kind of car.

Identify Conclusion
The conclusion is that Baumgartner’s incomplete evaluation of the environmental impact of two types of cars leads to a misleading comparison: “Baumgartner’s comparison of the environmental hazards of gasoline-powered cars with those of electric cars is misleading.”

A
Baumgartner makes a deceptive comparison between the environmental hazards of gasoline-powered and electric cars.
This is the conclusion. The argument demonstrates that Baumgartner’s lack of consideration for the use and recycling of cars causes a misleading comparison of the impacts of these cars. The rest of the stimulus supports the claim that Baumgartner’s comparison is misleading.
B
The use of a typical gasoline-powered car results in much greater resource depletion than does the use of a typical electric car.
This is a premise. The information in this answer provides support for the idea that understanding use, not just production, of different types of cars is necessary in order to compare their environmental impacts.
C
Baumgartner uses inaccurate data in his comparison of the environmental hazards of gasoline-powered and electric cars.
This claim is not supported by the argument, so it is not the main conclusion. The argument claims that Baumgartner is considering an incomplete set of information. This is not the same thing as inaccurate data.
D
The total life cycle of a product is what matters in assessing its environmental impact.
This is a premise that shows that Baumgartner’s comparison is misleading. Because the total life cycle is what matters, Baumgartner is using incomplete information when he only considers production. This answer supports the conclusion that Baumgartner’s comparison is misleading.
E
The production of gasoline-powered cars creates more environmental hazards than does that of electric cars.
This answer is not supported by the information provided, so it cannot be the main conclusion. From the information given, we don’t know if this is true.

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Over the last 10 years, there has been a dramatic increase in the number of people over the age of 65 living in this region. This is evident from the fact that during this time the average age of people living in this region has increased from approximately 52 to 57 years.

Summarize Argument: Phenomenon-Hypothesis
The author concludes that over the last 10 years, there has been a significant increase in the number of people over the age of 65 living in the region. This is based on the fact that over the last 10 years, the average age of people living in the region has increased from 52 to 57 years.

Notable Assumptions
The author assumes there’s no other explanation for the increase in average age besides an increase in the number of people over 65 living in the region. This overlooks the possibility that the average age increased simply due to younger people moving out of the region.

A
The number of people in the region under the age of 18 has increased over the last 10 years.
This provides evidence against the explanation that the average age increased due to younger people moving out. If the number of people under 18 went up, but the average still still increased, that strongly suggests there’s a lot more older people.
B
The birth rate for the region decreased significantly over the last 10 years.
If anything, this might weaken the argument by suggesting that we have fewer and fewer younger people in the region (due to fewer births). This would suggest the average age increase might be due simply to having fewer younger people.
C
The total number of people living in the region has decreased over the last 10 years.
This doesn’t tell us whether the decrease in population includes an overall decrease in younger people or in older people. If there are fewer younger people, (C) could end up weakening the argument.
D
The number of people who moved into the region over the last 10 years is greater than the number of those who moved out.
This tells us that the overall population has gone up. But this doesn’t help prove that the overall number of older people has significantly increased. (D) is consistent with very young people moving out and being replaced by a greater number of middle-aged people who aren’t over 65.
E
The average age for people in the region is higher than that for people in surrounding regions.
The argument is concerned with whether the average age increase in this reason allows us to conclude that this region has a greater number of people over 65. Other regions don’t affect this argument.

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The question stem reads: Which one of the following, if true, most weakens the argument? This is a Weaken question.

The author begins by describing how the laboratory experiment, which is the most effective method for teaching science, is disappearing from secondary school curricula. Instead of the laboratory experiment, students are simulating experiments using computers. We then see that the author believes this (simulating) experiments on computers) should be stopped, which is the author's conclusion. The reason the author gives is that the practice of simulating experiments in high school results in many students going to university without knowing how to work with laboratory experiments. We can reorganize the argument to read:

P1: High school students are using computers to simulate experiments.

P2: Using computers to simulate experiments results in many students going to university without knowing how to work with lab equipment.

C1: Simulating experiments should be stopped.

I highlighted the should to indicate that this conclusion is normative. Normative claims deal with good and bad. However, nothing is inherently good or bad about the world; determining what is good and bad requires us to make a value judgment. Is there anything inherently wrong with intentionally driving over a squirrel? You might argue that deliberately mowing down squirrels is wrong because it takes away life. Then I would ask you why taking away life is bad. You say it causes suffering. I say, what is wrong with suffering… and you see where I am going here. The upshot is that normative claims can only arise from other normative claims. If I have a normative claim in the conclusion, I need a normative claim in the premises.

The conclusion that we should stop simulating experiments in high school is normative, so I need to have a normative premise. However, the premises are descriptive; they describe a state of affairs. So what if kids go to college without knowing how to use laboratory equipment? There is nothing inherently wrong with that. The author assumes that it is a bad thing when we do not know if it is. To weaken this question, we need to look for an answer choice that suggests that going to college without knowing how to use laboratory equipment is not bad. The correct AC does not need to destroy the argument. It merely needs to cast doubt on the conclusion.

Answer Choice (A) says it is difficult for secondary schools to keep up with scientific knowledge without using computers. We have multiple issues. That might be true, but there is more to computer usage than just simulating experiments, so we do not know if this AC is even relevant to the argument. Even if we modified this (A) to say "difficult to keep up without simulating experiments," this would still be an incorrect AC. So what if it is difficult to teach students without computers? Just because something is easier for schools to teach using computers, that does not mean it is the right thing to do.

Answer Choice (B) is wrong on multiple counts. First, these schools might still have students simulate experiments on the computer and observe the teacher in other experiments. Even if there were mutually exclusive practices, the more critical issue is that the author's argument is entirely unconcerned with schools that do not simulate experiments on computers. The author merely wants to say that schools using computer simulations should stop.

Answer Choice (C) is irrelevant to the argument. The fact that computers are useful for teaching scientific terminology does not rule out computer simulations' bad downstream effects on university students. It can be true that both computers are useful for teaching scientific terminology, and using computers to simulate experiments is bad for students.

Answer Choice (D) is incorrect because the fact that secondary schools and universities have invested a lot of money into computers does not magically make using computers to simulate experiments acceptably. The author would simply reply, "That's unfortunate." (D) is the sunk cost fallacy.

Correct Answer Choice (E) because it identifies a reason that students going to college without knowing how to use lab equipment might be bad and rules that out. If not knowing how to use laboratory equipment makes students ill-prepared to learn science, that certainly seems bad. (E) rules that possibility out by saying students can learn just fine without knowing how to use lab equipment.


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The question stem reads: The career consultant's reasoning is most vulnerable to criticism on grounds that it. This is a Flaw question.

The consultant begins the argument by claiming the most popular career advice suggests emphasizing one's strengths and downplaying one's weaknesses to employers. The consultant then claims that research shows this advice to be incorrect. We have referential phrasing, so let's rephrase that claim to research shows emphasizing one's strengths and downplaying one's weaknesses to employers is bad advice. So if you are an employee, it is ill-advised to emphasize your good qualities and downplay your bad qualities, which is the consultant's conclusion.

Before we move forward, ask yourself what kind of research would provide the best evidence for the consultant's claim. Imagine if the consultant cited a study using dogs. Would you think that is excellent evidence for a claim about employees? Of course, you wouldn't because dogs are not the same as employees. Unless you are a Police K9, but let's not get too technical here. Good evidence would be research on employees. We want to be anticipating what the argument ought to say. If what the argument actually says deviates from what the argument ought to say, then bingo - we have found our flaw.

So what research does the consultant use? They say that a study of 314 managers shows that those who use self-deprecating humor in front of their employees are more likely to be seen by them (the employees) as even-handed, thoughtful, and concerned than those (the managers) who do not. Wait a minute, did the consultant just cite research about how managers present themselves to employees to conclude how employees should present themselves to employers? The argument uses evidence about one group to make a conclusion about another group. That is our flaw right there. Let's move to the answer choices.

Correct Answer Choice (A) is exactly what we identified as a flaw. When we map the stimulus onto (A), we get Bases a conclusion about how one group (managers) will respond to self-deprecation on information (the study of 314 managers) about how a different group (the employees) responds to it (self-depreciation). Bingo.

Answer Choice (B) is incorrect because the argument's conclusion is not about humor; the conclusion says that employees should not downplay weakness and emphasize strength. If the consultant's conclusion were about how managers should use (any type of) humor in front of their employees, then (B) would look better.

Answer Choice (C) is wrong because the research cited by the consultant says that managers who used self-deprecating humor were in a more positive light than managers who did not use self-deprecating humor. So the proposed problem in (C) is covered by the argument. (C) would look better if the stimulus said, "Managers who used self-deprecating humor were seen positively by employees," instead of comparing the managers who used the humor and those who did not. Even then, we would still run into the mismatch between employees and managers.

Answer Choice (D) is simply not done by the argument. Eliminate it.

Answer Choice (E) is the popular wrong answer, but I think that is primarily out of desperation. It is difficult to map this onto the stimulus. Those who picked (E) likely saw that the manager made a conclusion about the popular career advice (to emphasize strengths and downplay weaknesses). However, the evidence cited by the researcher is not a critique of that career advice. It is simply research.


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The question stem reads: The researcher's statements, if true, most strongly support which one of the following? This is a Most Strongly Supported Question.

The stimulus describes a study that occurred over six months. During those six months, the experimental group engaged in a daily afternoon exercise routine, while the control group engaged in "little to none." In an Ideal Experiment, the point of experimental groups and control groups is to isolate a "cause." In this problem, the experiment isolates "afternoon exercise" as a potential cause. So we can expect the experiment to produce results on the effects of "afternoon exercise." What effects does the stimulus state? Well, according to the study, the exercise group got 33% more deep sleep than the control group. The results here suggest that afternoon exercise leads to 33% more deep sleep than not exercising. Why? The stimulus says that exercising in the afternoon increases a person's body temperature before bedtime, and an increase in body temperature induces deeper sleep. So the proposed mechanism of action is that an increase in body temperature causes this deeper sleep, and exercise is one way to bring about that increase in body temperature.

Notably, while we have isolated exercise as an independent variable, we have no information on the body temperature of the control group. It is possible that the control group also experienced an increase in body temperature before bed by doing activities besides exercise. If that were the case, the study would suggest that the cause of the deeper sleep among exercisers might be something else other than the increase in body temperature. Perhaps exercise increases fatigue, and that’s actually the cause of deeper sleep.

The stimulus does not lead to any obvious prephase, so we can go ahead and dive into the answer choices using the process of elimination.

Answer Choice (A) makes multiple mistakes. First, the study suggests that afternoon exercise is sufficient (enough) to bring about this 33% increase in deep sleep. That doesn’t mean it is required. There may be additional ways to bring about an increase in deep sleep without exercise. Second, we know nothing about what constitutes "adequate deep sleep." We know that the exercise group got more deep sleep compared to the control group. However, we do not know if that is an adequate amount of deep sleep. It’s possible both groups got an adequate amount of deep sleep. It’s possible both groups failed to get an adequate amount of deep sleep.

Answer Choice (B) makes a very strong claim. The study is limited just to the effects of afternoon exercise on deep sleep. We have no data to support any claims about morning exercise. Since we can’t infer this information from the stimulus, (B) isn’t supported.

Answer Choice (C) makes an error by drawing a general claim from a specific case. We cannot draw conclusions about the "best" way to achieve something from a single instance. The stimulus claims that increasing body temperature is one way to induce deeper sleep, but we cannot then conclude that it is the "best" way, so (C) isn’t supported.

Answer Choice (D) claims that no one in the control group experiences a rise in body temperature. We discussed earlier how we do not know if this is the case, so (D) is incorrect.

Correct Answer Choice (E) says that raising body temperature with a warm bath before bedtime would likely lead to deep sleep. This looks great. The stimulus says that extra heat induces deeper sleep, which supports the idea that a warm bath would lead to deeper sleep. Why? Because the bath increased the body temperature.Therefore, this answer choice is supported based on the information in the stimulus.


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