Summary
The Rienzi sank because it had a hole. It descended rapidly. Usually, ships that sink this fast don’t fully flood by the time they reach the ocean floor, which makes them implode. The Rienzi did not implode. Sabotage can cause a ship to flood fully.
Notable Valid Inferences
The Rienzi must have fully flooded by the time it was deep in the ocean—we know this because if it hadn’t flooded fully, it would have imploded. We cannot conclude what caused the full flooding, but we can infer that it was either sabotage or that the Rienzi filled with water faster than normal.
A
The Rienzi was so constructed as to reduce the risk of sinking by impact.
This could be false. The stimulus does not offer any information about how the Rienzi was constructed.
B
If the Rienzi became fully flooded, it did so only after it reached the ocean floor.
This must be false. We know the Rienzi must have fully flooded when it reached the ocean floor or it would have imploded.
C
If the Rienzi was not sunk by sabotage, water flooded into it unusually fast.
This must be true. We know the Rienzi fully flooded by the time it reached the ocean floor—this means it was either sabotaged to allow for full flooding or water entered the ship faster than normal.
D
If the Rienzi had sunk more slowly, it would have imploded.
This could be false. We don’t know if the rate at which the Rienzi sunk caused the ship not to flood fully, and whether changing the rate would affect this outcome.
E
The Rienzi was so strongly constructed as to resist imploding under deep-sea pressure.
This could be false. The stimulus does not offer any information about how the Rienzi was constructed.
Summarize Argument
The author concludes that athletes’ use of nonaddictive drugs should not be banned. As support, the author claims that almost everything in sports is unnatural (and that many things are permitted despite being unnatural). The author also says that focus should be on more serious issues in sports that result in deaths and injuries instead of focusing on banning nonaddictive drugs because they are unnatural.
Notable Assumptions
The author assumes that nonaddictive drugs are not physically harmful and do not result in injury or death. Additionally, the author just rejects one reason to ban nonaddictive drugs, then claims that nonaddictive drugs should not be banned. The most that the author has done is demonstrate that nonaddictive drugs should not be banned on the basis of being unnatural; there could be other reasons why nonaddictive drugs should be banned.
A
Massive doses of aspirin and vitamins enhance athletic performance.
The examples of tools given by the author (high-tech running shoes and specialized machines) also enhance athletic performance. The author isn’t saying that things that enhance athletic performance should be banned; the author is just saying that nonaddictive drugs shouldn’t be banned.
B
Addictive drugs are just as unnatural as nonaddictive drugs like aspirin and vitamins.
The author believes that addictive drugs should be banned. But this is because they are physically harmful, not because they are unnatural. Also, the argument concerns nonaddictive drugs, so additional information about addictive drugs does not weaken the argument.
C
Unnecessary deaths and injuries occur in other walks of life besides modern sports.
The argument is about whether or not nonaddictive drugs should be banned in sports; risk of death or injury in other areas of life is completely irrelevant to the specific claims made in this argument.
D
There would be more unnecessary deaths and injuries if it were not for running shoes, boxing gloves, and bodybuilding machines.
(D) demonstrates some benefits of other unnatural tools used in sports; this does not weaken the argument. This actually gives a reason that some unnatural things have a positive role in sports.
E
Taking massive doses of aspirin or vitamins can be physically harmful.
The author accepts that addictive drugs are banned because they are physically harmful; there is no information given on the physical impacts of nonaddictive drugs. If nonaddictive drugs are physically harmful, the argument that they shouldn’t be banned is much weaker.
Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that a small republic’s military recruitment rate for 18-year-olds is largely dependent on the recruitment rate for high school dropouts. This hypothesis is based on an observed correlation over 6 years: as the proportion of high school dropouts increased, so did the recruitment rate for 18-year-olds. Additionally, 18-year-olds in the republic are usually either high school graduates or dropouts.
Notable Assumptions
The author assumes that just because the proportion of dropouts and the recruitment rate for 18-year-olds increased at the same time, most 18-year-old military recruits are dropouts. In other words, the author assumes that the correlation was caused by the military being able to recruit more dropouts, and that they weren’t instead recruiting more graduates.
A
A larger number of 18-year-old high school graduates were recruited for the republic’s armed services in 1986 than in 1980.
This does not weaken the argument, which is about proportions and rates, not about absolute numbers. The number of 18-year-old graduate recruits increasing implies nothing about their recruitment rate, which could have increased, decreased, or stayed the same.
B
Many of the high-technology systems used by the republic’s armed services can be operated only by individuals who have completed a high school education.
This does not weaken the argument because who is able to operate military technology is unrelated to who the military is able to recruit. We also don’t know how many people are needed to operate the tech: maybe it’s just a few, so they could still mostly recruit dropouts.
C
Between 1980 and 1986 the percentage of high school graduates among 18-year-olds recruited in the republic rose sharply.
This weakens the argument, because it rebuts the author’s assumption that the observed correlation implied a causal link. This instead shows us that the increased recruitment rate was not dependent on recruiting more dropouts, but rather more graduates.
D
Personnel of the republic’s armed services are strongly encouraged to finish their high school education.
This does not weaken the argument, because the domain of the argument is limited to who the republic’s military is recruiting. Whatever education people pursue after they have already been recruited is irrelevant.
E
The proportion of recruits who had completed at least two years of college education was greater in 1986 than in 1980.
This does not weaken the argument, because the argument is purely about 18-year-old recruits, who we already know are usually either high school graduates or high school dropouts. Recruits who join later, after several years of college, are outside the argument’s domain.