Summary
The argument concludes that passengers are safer on airplanes with a collision-evasion system equipped, even though the system frequently warns pilots of phantom airplanes. This is supported by the premise that the system warns pilots to evade possible collisions.
Notable Assumptions
The argument assumes that the phantom warnings don’t create more danger than the system prevents. For example, that pilots don’t take dangerous evasion maneuvers in response to phantom warnings.
It also assumes that pilots actually respond to the system’s warnings frequently enough to avoid possible collisions. Otherwise, the system’s presence wouldn’t make much difference to safety at all.
It also assumes that pilots actually respond to the system’s warnings frequently enough to avoid possible collisions. Otherwise, the system’s presence wouldn’t make much difference to safety at all.
A
Passengers feel no safer on airplanes equipped with the radar system than on comparable airplanes not so equipped.
Whether or not passengers feel safer isn’t important to determining whether or not they are safer—in fact, it’s not relevant at all.
B
Warnings given by a collision-avoidance system about phantom airplanes are not caused by distorted radar signals.
The possible cause of phantom airplane warnings doesn’t make any difference to the argument, so can’t be necessary.
C
The frequency of invalid warnings will not cause pilots routinely to disregard the system’s warnings.
For the argument to make sense, pilots have to actually act on the system’s warnings—otherwise the system would make no difference. If we negated this, meaning pilots just ignored the warnings, that would leave the conclusion unsupported.
D
Commercial passenger airplanes are not the only planes that can be equipped with a collision-avoidance system.
Whether or not the system can be equipped on other types of planes is irrelevant to whether it makes commercial air passengers safer.
E
The greatest safety risk for passengers traveling on commercial passenger airplanes is that of a midair collision.
The argument just claims that passengers are safer with the system than without it. Whether that means they’re a lot safer or a little safer doesn’t really matter, so this isn’t a necessary assumption.
Summary
The author concludes that the best way to teach history is to spend most class time on the lives of historical figures and very little time on dates and statistics.
Why?
Because most students are bored by history courses as they’re usually taught. The usual way is to spend a large amount of time on dates and statistics.
Why?
Because most students are bored by history courses as they’re usually taught. The usual way is to spend a large amount of time on dates and statistics.
Notable Assumptions
The author assumes that spending most class time on recounting the lives of historical figures is NOT just as boring as spending a large amount of time on dates and statistics.
Also, the author assumes that boring students is something that detracts from the effectiveness of teaching history.
Also, the author assumes that boring students is something that detracts from the effectiveness of teaching history.
A
One should avoid boring one’s students when teaching a history course.
Necessary, because if it weren’t true, then the fact the current method of teaching history is boring wouldn’t constitute a reason a different way would be better.
B
It is not incompatible with the attainable goals of teaching history to spend very little class time on dates and statistics.
Necessary, because if it IS incompatible with the attainable goals of teaching history to spend little class time on dates and statistics, then the author’s proposed “best way” to teach wouldn’t be the best way to teach history.
C
It is possible to recount the lives of historical figures without referring to dates and statistics.
Not necessary, because the author doesn’t conclude that the best way to teach history is to completely avoid referring to dates and statistics. The conclusion is just that the best way involves spending “very little” time on dates and statistics.
D
It is compatible with the attainable goals of teaching history to spend most class time recounting the lives of historical figures.
Necessary, because if the author’s proposed method of teaching history is NOT compatible with the attainable goals of teaching history, then the method would not constitute the best way of teaching history.
E
Students are more bored by history courses as they are usually taught than they would be by courses that spend most class time recounting the lives of historical figures.
Necessary, because if students are NOT more bored by the usual method than they would be by the author’s proposed method, then the premise no longer provides a reason to think that the proposed method is better. What the author proposes would be just as boring.
Hudson: By your reasoning I cannot help but become rich, because there is similarly no such thing as my dying before my first million dollars is in the bank.
Summarize Argument: Counter-Position
In response to Whittaker’s claim that there is no such thing as the number of medical students who drop out before the second year, Hudson similarly concludes he cannot help but become rich. As evidence, he states there is no such thing as dying before his first million dollars is in the bank.
Describe Method of Reasoning
Hudson counters the position held by Whittaker. He does this by presenting an analogous argument with an obviously false conclusion.
A
showing that a relevantly analogous argument leads to an untenable conclusion
The analogous argument is Hudson’s comparison between there being no such thing as medical students dropping out before their second year and no such thing as himself not becoming rich.
B
citing a specific example to counter Whittaker’s general claim
Hudson does not cite any specific example. His analogous argument is stated generally and theoretically.
C
pointing out that Whittaker mistakes a necessary situation for a possible situation
Hudson does not think that Whittaker’s conclusion is a possible situation. His analogous argument seeks to establish that Whittaker’s conclusion is absurd.
D
claiming that what Whittaker says cannot be true because Whittaker acts as if it were false
Hudson does not address Whittaker’s actions.
E
showing that Whittaker’s argument relies on analyzing an extreme and unrepresentative case
Whittaker’s argument did not analyze any one specific case.
Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that the overall driving-age population of Australia must have more skillful drivers now compared to five years ago. This is based on the fact that, even though the driving age population has grown over the last five years, the annual number of traffic deaths has gone down over that time.
Notable Assumptions
The author assumes that there’s no other causal explanation for the decrease in annual traffic deaths other than an increase in the skill of drivers.
A
Three years ago, a mandatory seat-belt law went into effect throughout Australia.
This is a potential alternate explanation for the decrease in traffic deaths. Maybe the law caused more people to wear seat belts, which saved more lives.
B
Five years ago, Australia began a major road repair project.
This is a potential alternate explanation for the decrease in traffic deaths. Maybe repairs improved road quality, which allowed for safer driving.
C
Because of increases in the price of fuel, Australians on average drive less each year than in the preceding year.
This is a potential alternate explanation for the decrease in traffic deaths. Maybe average time spent driving went down, which we’d expect to result in fewer deaths from driving.
D
The number of hospital emergency facilities in Australia has doubled in the last five years.
This is a potential alternate explanation for the decrease in traffic deaths. Maybe the increase in emergency facilities made it easier to get to the hospital after an accident, which we’d expect to reduce the number of deaths from those accidents.
E
In response to an increase in traffic fatalities, Australia instituted a program of mandatory driver education five years ago.
We can interpret this as supporting the author’s hypothesis. The driver education program could have contributed to more skillful drivers in the population. Since we can read this as supporting the author’s hypothesis, it’s the correct answer to this Weaken-EXCEPT question.