Reading ComprehensionDifficulty: Hard

PT17 S4 P3 Q17 Explanation

Carbon Tax

A free, expert breakdown of this official LSAT Reading Comprehension question.

TopicsLocal PurposeSociety

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Passage

One way governments can decrease air pollution is to impose a tax on industrial carbon dioxide emissions. But why should governments consider a carbon tax when they could control emissions by establishing energy efficiency and conservation standards, by legislating against coal use, or by increasing investment in nuclear power? The great virtue fuels for those carrying a higher tax, and also to reduce the total use of energy.

However, it is not clear how high such a tax should be or what its economic and environmental implications would be. At first glance, it is not difficult to estimate roughly the size of the tax needed to effect a given level of emission reduction. One writer estimates, for example, that a also based on the assumption that all countries will behave cooperatively in imposing a carbon tax.

There are very strong reasons to believe that cooperation would be difficult to win. If most countries cooperated, then any country that chose not to cooperate would be advantaged: it would have no abatement costs, and the effect on the environment of its defection would be relatively small. Because needed to reduce carbon dioxide emissions might prove elusive.

Should countries act unilaterally to curb emissions? If a country were to act unilaterally, the benefits would be spread across the globe, whereas the costs would fall solely on the country taking the action. The action would reduce emissions globally, and the effect of this would be to reduce the benefit other emission reduction may not be lost, but it would surely be diminished by this free-riding behavior.

What this question is testing

Local Purpose

Your task

Identify why the author included the referenced detail at that point in the passage — its function, not its content.

Common trap

Answers that merely repeat or summarize the topic of the detail instead of describing the role it plays.

Winning move

Ask what job the detail does for the paragraph, then for the passage's broader point.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
17.

The author mentions the estimates of “One writer” (second paragraph) primarily in

Answer choices

  1. Correct38% picked this

    indicate in a general way the size that a carbon tax must be for it

    Why this is right

    When we're picking answers to Local Purpose questions, we're hoping to see a match between the answer and the bigger idea in the previous sentence. "Indicate in a general way" matches up well with "to estimate roughly" from the 2nd sentence of the 2nd paragraph. "the size that a carbon tax must be for it to be effective" matches up well with "the size of the tax needed to effect a given level of emission reduction", from that same sentence.

    Skill tested: Local Purpose · how this choice captures the passage's function is the move to repeat next time.

  2. Too Strong: most accurate / practical4% picked this

    provide the most accurate information available about the most practical size for

    The author wasn't suggesting anything this extreme. This is just one writer with one rough estimate. Our author isn't selling this writer's estimates as "the most accurate / most practical".

  3. Wrong Purpose13% picked this

    suggest that the target recommended by the 1988 Toronto Conference is

    The author was never saying that the Toronto target was unrealistic. The author was saying, "If, for example, you wanted to effect the level of emission reduction targeted by the Toronto Conference, then you'd need about 41% on coal, 33% on oil, 25% on gas."

  4. Wrong Purpose6% picked this

    undermine the argument that a carbon tax would provide incentives for users to

    The author talks about certain countries having an undermined incentive to achieve emission reductions (if other countries are solving global warming for you, you can just free-ride). But that's in paragraph 3 and 4. This question is only about the beginning of paragraph 2. And the author is never herself trying to undermine the argument that a carbon tax would provide incentives. She's just (much later in the passage) discussing the unfortunate reality that we would need to account for "free-riders".

  5. Out of Scope: how it's calculated40% picked this

    show how the size of an effective carbon tax can

    Presenting the writer's estimates is presenting that writer's calculation. It's not presenting "how it was calculated". Presumably, the writer took into account different emission levels of coal / oil / gas, and looked at the 20% emissions reduction, looked at previous consumer behavior in response to tax increases, etc. The passage doesn't present any of that story of the process behind the calculation. The author brings up "one writer" to show that the size can be calculated not to show how the size can be calculated

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