Logical Reasoning

PT21 · S2 · Q7 Brownlea’s post office must be

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Brownlea’s post office must be replaced with a larger one.

Conclusion (clearly)

The post office could be built more cheaply on the outskirts of town.

Evidence (since)

The cost of acquiring a site is a significant part of the total construction cost.

Land near the town center is more expensive than land on the outskirts of town.

Evaluate

Given that ... cost of acquiring a site is a big part of total construction cost and land on the outskirts of town is cheaper,

How could we still argue that ... the post office could be built more cheaply closer to the town center? (i.e. not on the outskirts)

This is a Comparative argument, since the conclusion is literally a comparative claim (building on outskirts is cheaper than center of town). We need to know all the factors involved in building a post office on the outskirts vs. in the center of town.

So far we only know one part of the construction cost: buying the parcel of land is cheaper on the outskirts.

The center of town might still be cheaper overall, if there are other aspects of construction costs that tilt in favor of the city center. What if the labor costs are cheaper for construction workers? What if there are tax incentive to build in the center of town? What if it's easier to ship the raw materials to the center of town.

Goal

Look for some other aspect of construction cost that might be more expensive on the outskirts, cheaper towards the town center.

Which one of the following, if true, most seriously undermines the argument’s stated conclusion?

The new post office will
No Impact
Since this building code is citywide it affects town-center and outskirts equally. We need a factor that is better for town-center construction, worse for outskirts construction.
5% picked this
Correct
If the new post office
Why this is right
This isn't much of a cost savings, but it's something! No other answer gives us a better option. Building a parking lot is definitely more expensive than not building a parking lot. On Weaken, we usually want to be able to say, Even though [evidence is true], still possible [anti-conclusion] is true, because [answer choice]. Even though it's cheaper to buy land on the outskirts (which is a big part of construction cost), it's still possible that building on the outskirts of town isn't cheaper, because if we build on the outskirts we'll also have to build a parking lot.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
69% picked this
If the new post office
No Impact
It's not clear that anything in this answer adds to "building costs", which is all we're analyzing. This conclusion isn't saying that it will be cheaper for the city to have the post office in the outskirts or that it will be cheaper to run / maintain the post office in the outskirts. It's only about how cheaply it can be built. Expanding city bus routes has nothing to do with "total construction cost" for a post office.
12% picked this
If the new post office
No Impact
It's not clear that anything in this answer adds to "building costs", which is all we're analyzing. This answer is just making it sound like the post office might end up spending more money in their efforts to service a post office on the outskirts of town, but the argument is solely about the cost of constructing the new post office.
13% picked this
If the new post office
Strengthens, if anything
This is telling us something negative about building the post office in the city center, which is the opposite of what we want. It's not clear that having to do some work at night or on weekends would actually be more expensive than daytime work (in real life, you probably do have to pay workers more for those inconvenient hours), but even on a gist-y level, the fact that we're hearing about something challenging / hard / bad when it comes to building in the town center means this is nowhere near what we want (which is something that would make building in the town center cheaper than building on the outskirts).
1% picked this

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