Necessary Assumption weeeee

stimulus:

1. Repressors (unconscious inhibition) have increased heart rate in emotion-provoking situations.

2. Nonrepressors (conscious inhibition) experience the same thing.

Conclusion: Inhibition is the reason for the sharp rise in heart rate.

Answer A is correct because it must be true that emotion-provoking situations are not a factor in causing heart rates to rise. We know that heart rates are rising in emotion provoking situations, but we don't know if its the situation or the inhibition of emotions (holding that unconscious and conscious does not matter) that is causing the reaction. Eliminating the emotion-provoking situation factor allows the conclusion (inhibition) to be true without possible alternative explanations.

yay!

Necessary assumption question!

stimulus can be summarized to:

1. Brown dwarfs are hot enough to burn hydrogen.

2. Stars have substantial amounts of lithium when first formed.

3. All stars, except the coolest brown dwarfs, are hot enough to destroy lithium completely.

Conclusion: Any star that has no lithium is not one of the coolest brown dwarfs.

Answer A is correct because it states that:

All coolest brown dwarfs have never been hot enough to destroy lithium.

This answer must be true because if a coolest brown dwarf has been hot enough to destroy lithium, the conclusion fails completely.

Simpler:

1. Golden retrievers like to eat bones.

2. Dogs grow baby teeth when they are puppies.

3. All dogs, except tiny golden retrievers, lose all their baby teeth.

Conclusion: Any dog that has no baby teeth is not a tiny golden retriever.

Answer A would act as:

All tiny golden retrievers have never lost all their baby teeth.

yay :D

Strengthen question- enhance the support relationship between the premise and conclusion.

stimulus can be broken down:

premise: success is easier if you genuinely believe in yourself.

conclusion: if you want to succeed, you need to act as if you are genuinely confident.

Answer B enhances the relationship because it bridges the gap between genuine belief in self and acting as if genuine confident.

Analogy:

premise: getting the job is easier if you smile often.

conclusion: if you want the job, you need to act as if you love to smile.

strengthener: Acting like you love to smile will cause you to smile often.

Weaken!

The stimulus can be summarized as so:

1. Sun was only 80% as bright back then compared to today.

2. If we had the same 80% sun today, our oceans would be frozen BUT there's evidence that somehow the oceans were still liquid back then.

3. Heat is trapped within the Earth's atmosphere through the presence of co2 (like methane), aka a greenhouse gas.

4. Only way oceans could have been liquid is if the greenhouse gases were higher back then.

Conclusion: Co2 must have been higher back then compared to today.

AC B weakens this conclusion because it proposes an alternative greenhouse gas that could have contributed to the trapping of heat within the atmosphere- which makes the increase of co2 as claimed less likely.

Have to avoid the trap of reading the stimulus as if co2 is the only greenhouse gas:

(Heat is trapped within Earth's atmosphere through the presence of carbon dioxide, which, like methane, is a "greenhouse gas.")

It would have been different had it claim that co2 was the ONLY greenhouse gas that trapped heat within Earth's atmosphere.

yahoo!

Most Strongly Supported: find the conclusion in the AC.

the stimulus can be diagrammed as so:

1. manners -> social

2. morals -s-> social AND morals -s-> /social

3. etiq -> /alone

what we can infer from this:

• alone -> /social

  etiq -> social -> manners

• morals can be social or unsocial

Answer A is correct because it states that:

moral -s-> /social

Parallel flaw question :D

the stimulus can be diagrammed as so:

1. mutations frequent -> evolution adaptation

2. dramatic environ change -> evolution adaptation

Conclusion: mutations frequent -> dramatic environ change

simpler:

1. A-> B

2. C-> B

Conclusion: A-> C

Answer C makes the same flaw:

1. honest -> tell truth

2. moral upright -> tell truth

Conclusion: honest -> moral upright

yay!

@RileyHelm Hi Riley. Although the stimulus didn't mention the reproducing of a signal from a digital perspective, it did mention the duplication processes in an analog system. It can be summarized as the duplications from an analog representation will continue to have smaller variations from the original the more times it is replicated, until it will one day become too different from the original.

Answer E is most strongly supported because the stimulus already provides with us that "digital systems cannot produce signals that are more precise than their digital units" AKA they are represented by numbers and only numbers. The duplication of numbers will not lose its original representation because it is not "infinitely detailed" like analog systems that can lose their detailed value over replications as mentioned earlier. That's why they were preferable to analog systems in situations where their signal has to be replicated multiple times.

This is how I imagined it:

Analog System: handcrafted wood clock

Digital System: digital clock

It's harder to replicate a handcrafted wood clock multiple times without creating variations/errors over time, compared to a digital clock where the digital numbers are forever consistent.

Hope this helps! :)

lol how is this a one star!! it felt like at least 3 -_- anyways-

This is a necessary assumption question. Find the AC that must be true or else the falsity of it would destroy the argument.

Stimulus summarized:

• A test to see if someone has been infected by T already is by injecting them with a protein from T.

• If someone is already infected by a bacterium, their body will recognize it and attack it- hence the skin irritation wherever it's injected.

Conclusion: Physicians agreed that anyone who gets skin irritation from the injection site has already been infected with T.

Answer C is the correct answer.

This is because it must be true that the proteins in T are exclusive to T. AKA no other bacteria shares the same protein that could create the same reaction. This is NECESSARY because if Bacteria X created the same reaction in the presence of the same protein- there would be no way to know if its Bacteria X or tuberculosis that is causing the skin irritation.

Sufficient Assumption question- need an answer that will allow the conclusion to be true.

The premises can be diagrammed as so:

1. replacement parts hard to obtain -> install new sirens

2. install new sirens -> enhanced public safety

3. replacement part company out of business.

Conclusion: If P2 is true, the public will indeed be safer.

*Need to connect P3 to P1 so that we can draw the conclusion as stated in P2 (enhanced public safety).

Answer D:

cannot get parts from replacement part company -> replacement parts hard to obtain

This answer allows us to draw the conclusion that the government will install new sirens -> enhanced public safety.

Simpler Diagram:

1. A -> B

2. B -> C

3. /D

Conclusion: C

Answer D:

/D -> A

This allows the conclusion to drawn because we know that the old sirens will be difficult to obtain.

Interested!

Interested!

Interested!

Interested!

Almost chose C, but changed to D last second.

Realized that C is only attractive because the stimulus talks about how "different foods contain nutrients that are helpful for treating or preventing different health problems". However, it does not necessarily support the statement that any two people have different health problems. It only supports the fact that different foods have different nutrients for people with various needs. Not anything about the comparison of health problems between people.

D is correct because it is strongly implied that fad diets lack the nutrients in different foods because they "prescribe a single narrow range of nutrients". The argument goes on to then encourage people to eat plenty of fruits and vegetables, aka eat different foods containing different nutrients.

D is the correct answer.

The question calls for an answer that weakens the argument.

The stimulus can be broken down into:

• heavy salting of Albritten started 20 yrs ago

• now the groundwater has 100mg per liter

• nearby city with no salting only has 10mg per liter

• 250mg+ per liter will be too salty

• THEREFORE, if we keep salting Albritten, the water will be too salty to drink in the next few decades.

D is the correct answer because it offers the idea that Albritten's water was already salty 20 yrs ago (90mg vs 100mg today). It cannot be the salting that made it raise in saltiness.

This weakens the argument because if the saltiness is due to something else besides the salting, the continued salting of the roads will not necessarily render the water unpalatable in the next few decades.

E is the correct answer.

The stimulus can be diagrammed as so:

beautiful -s-> Persian cat -> pompous -> irritating

The question calls for an answer that must be false.

E states that:

irritating + beautiful -s-> /Persian

which cannot be true because the contrapositive of the stimulus is:

/irritating -> /pompous -> /Persian Cat

This is the only possible way to get to the conclusion /Persian cat. Therefore, E must be false.

B is the correct answer.

Stimulus can be understood as:

• some criminals with good motives deserve less severe punishments

• motives can be faked and disingenuous

• THEREFORE, judges should not lessen punishment on the basis of motives

We need a rule that allows the conclusion to be drawn. The rule must have the outcome that criminals will deserve punishment that is not mitigated on the basis of motives.

B is the correct answer because it establishes that the author believes that it is better for judges to give harsher punishments than lenient ones to reduce the risk of being swayed by disingenuous motive projections.

Simply,

lets say someone was caught stealing food just for the thrill of stealing. however, in front of the judge, they present their motives as stealing food to feed their hungry family. to reduce the risk of giving them an unfair punishment (one lesser than the one they deserve), AC B's rule states that it is better to always give harsher punishments. This is in line with the author's statement that motives should not be a determining factor for punishment.

C is the correct answer.

The question calls for a necessary assumption.

Stimulus can be diagrammed as below:

generators -> convert heat to electricity

steel -> leftover heat

--------------------

steel + generators -> save money on electricity

AC C provides that + generators will cover the cost of themselves. If purchasing generators would cost the engineers money out of pocket, it would not make sense for the conclusion to be that they would reduce their electric bills. Therefore, C must be true for the conclusion to follow.

A is the correct answer.

Stimulus can be diagrammed as so:

<50 ppl + >25% dup -> /funded

>25% dup

--------------

funded

Take the contrapositive:

funded -> /<50 ppl OR />25% dup

• since it is provided that it will duplicate more than 25% of the existing material, it must be that there are at least 50 people or more available for hire.

C is the correct answer.

Simply, the argument can be understood as:

very large (class sizes + teaching loads) = not good

------------------

very large + very small (class sizes + teaching loads) = not good

It is clear then, that we are missing a premise that describes why very small class sizes and teaching loads are bad, which C very explicitly states.

Yay!

A is the correct answer.

"responses collected at one time from many individuals of widely different ages" = survey

projected to

"hypothetical earlier responses of a single individual at some of those ages" = 48 year old man example, which kept referencing him to subsequent younger ages

A is the correct answer.

The question calls for an answer that is most strongly supported.

From the stimulus, we know that:

• Mature white pines:

  • intercept almost all sunlight

  • leave a deep litter

  • grow to great heights that leave little light to floor

  • white pines cannot grow in their own shade

We are to find an answer that is compatible with the situation where a dense forest has a stand of trees of which are all mature white pines.

A is the correct answer- we need to remember that since mature white pines are so greedy for sunlight, they don't allow opportunity for young trees to regenerate. It must follow that the trees standing now all came about around the same time, so that at the time they were all pre-mature, they were able to share resources/sunlight and not outcompete each other.

Lets breakdown A:

the ages of the tree in the stand do not differ from each other: lets assume they are all around 20 years old

the length of time it takes a white pine to grow to maturity: lets assume 10 years

A says, the ages of the trees in the stand do not differ by more than 10 years old- which means that they must have all had opportunity to grow and regenerate before there were established mature white pines (who would've prevented their growth). The difference in their ages do not exceed 10 years. There cannot be a tree which is 5 years old among the 20 year old trees because there would not have been enough sunlight for them to regenerate.

B is the correct answer.

The stimulus tells us:

• Wholesale price of one bottle has always been the same.

• Profit: Wholesale price minus costs

• All costs of producing bottle has been constant EXCEPT corks (x2 from before)

From this, we can infer that the bottles being sold today must bring in LESS profit.

Why?

Take for example:

1991:

Wholesale price: $10

Profit: $10- $3 (other costs) - $1 (cork fee) = $6 profit

Today:

Wholesale price: $10

Profit: $10- $3 (other costs) - $2 (cork fee) = $5 profit

* It must be true that the profits from each bottle TODAY is less than 1991.

Wow!! Thank you so much @J.Y.Ping and 7Sage team!! 🥺 I recently implemented all the older PTs into my drills and saw that there were zero comments for most, if not all of them. I started commenting my own personal processes in hopes of giving others a place to start if they ever decided to try older PT questions too. Never thought that it would get noticed!!

B is the correct answer.

The stimulus can be understood as so:

forest fires protect forests and their ecosystems

---------------------------------

/attempt to control

The question calls for a sufficient assumption AC that will allow the premises to connect to the conclusion.

AC B can be understood as:

attempt to control forest fire -> protection of ecosystem

more importantly, the contrapositive:

/protection of ecosystem -> /attempt to control forest fire

The connection has to be made that forest fires are in and of themselves protecting the ecosystem by helping them flourish through the facility of spreading seed pods, preventing overabundance of insects, etc. If we were to prevent the flourishing of forests, it would be detrimental to their ecosystems.

Therefore, the contrapositive of AC B states that if the ecosystem is not in need of protection, then human beings should not attempt to control forest fires.

Fitted into the stimulus:

forest fires protect forests and their ecosystems aka: /protection of ecosystem

/protection of ecosystem -> /attempt to control forest fire

---------------------------------

/attempt to control