The emission of sulfur dioxide when high-sulfur coal is burned is restricted by law. New coal-burning plants usually comply with the law by installing expensive equipment to filter sulfur dioxide from their emissions. These new plants could save money by installing instead less expensive cleaning equipment that chemically removes most sulfur from coal before combustion.
Which of the following, if known, would be most relevant to evaluating the claim above about how new coal-burning plants could save money?
A. Whether existing oil-burning plants are required to filter sulfur dioxide from their emissions
B. Whether the expense of installing the cleaning equipment in a new plant is less than the expense of installing the cleaning equipment in an older plant
C. Whether the process of cleaning the coal is more expensive than the process of filtering the emissions
D. Whether lawful emissions of sulfur dioxide from coal-burning plants are damaging the environment
E. Whether existing plants that use the filtering equipment could replace this equipment with the cleaning equipment and still compete with new plants that install the cleaning equipment
OA: C
can someone explain this one~?
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Sulfur Dioxide--Evaluation
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amysky_0205
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ceilidh.erickson
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When we want to EVALUATE a conclusion, we need to look for the LOGICAL GAP between the premises and the conclusion.
Premises:
- emission of sulfur dioxide from burning high-sulfur coal is restricted
- new plants usually install expensive equipment to filter sulfur dioxide form emissions
Conclusion:
Plants could save money by installing less expensive equipment that removes sulfur before combustion
Logical Gap:
What about other factors that affect cost? We're given info about comparative equipment costs, but those aren't the only costs involved. What if the process or the labor costs more? Or if we'd need to use more coal? To evaluate whether they'd save money, we need information about other costs.
A. Oil-burning plants are irrelevant to the cost of coal-burning plants
B. The comparison of new plants v. old plants is a false comparison (a common CR wrong answer type). The conclusion specifically claims that "new plants could save money," so we don't care about the old ones.
C. This speaks to another cost - the cost of the process! This speaks to the logical gap that we were missing, so it is useful to evaluate. CORRECT
D. In the context of the argument, we don't care about what the emissions are doing to the environment (although hopefully we care in real life!). It's not relevant to this conclusion, so it's out.
E. Again, our conclusion specifically addresses NEW plants, so we don't care what existing plants do, or whether they can compete.
Premises:
- emission of sulfur dioxide from burning high-sulfur coal is restricted
- new plants usually install expensive equipment to filter sulfur dioxide form emissions
Conclusion:
Plants could save money by installing less expensive equipment that removes sulfur before combustion
Logical Gap:
What about other factors that affect cost? We're given info about comparative equipment costs, but those aren't the only costs involved. What if the process or the labor costs more? Or if we'd need to use more coal? To evaluate whether they'd save money, we need information about other costs.
A. Oil-burning plants are irrelevant to the cost of coal-burning plants
B. The comparison of new plants v. old plants is a false comparison (a common CR wrong answer type). The conclusion specifically claims that "new plants could save money," so we don't care about the old ones.
C. This speaks to another cost - the cost of the process! This speaks to the logical gap that we were missing, so it is useful to evaluate. CORRECT
D. In the context of the argument, we don't care about what the emissions are doing to the environment (although hopefully we care in real life!). It's not relevant to this conclusion, so it's out.
E. Again, our conclusion specifically addresses NEW plants, so we don't care what existing plants do, or whether they can compete.
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education
EdM in Mind, Brain, and Education
Harvard Graduate School of Education
