Question 210·Medium·Rhetorical Synthesis
While preparing a presentation, a student has compiled the following notes about replacing high-pressure sodium (HPS) streetlights with light-emitting diode (LED) streetlights:
- A typical HPS bulb lasts about 24,000 hours.
- An LED streetlight can operate for up to 50,000 hours.
- LED fixtures use roughly 40% less electricity than HPS fixtures.
- Municipal crews must close lanes to change burned-out bulbs.
- Fewer replacements mean lower labor and equipment costs.
The student wants to emphasize how switching to LED streetlights can reduce maintenance costs. Which choice most effectively uses relevant information from the notes to accomplish this goal?
For rhetorical synthesis questions, start by underlining the stated goal in the prompt (here, emphasizing reduced maintenance costs). Then quickly sort the given notes into categories (e.g., maintenance vs. energy) and decide which category directly supports the goal. Evaluate each answer choice by asking: (1) Does it clearly match the goal’s focus? (2) Does it use the most relevant notes without adding unrelated ideas? Eliminate choices that drift to a different topic (like energy use when the question asks about maintenance) or that state facts without explaining the required cause-and-effect. This targeted matching keeps you fast and accurate.
Hints
Restate the goal in your own words
The question isn’t asking about energy savings in general. Put the goal into your own words: the sentence should explain how LEDs save money specifically on maintenance work (like replacing bulbs and closing lanes).
Sort the notes into categories
Look at the bullet points and decide which ones are about maintenance/replacement and which are about electricity/energy use. Focus on the maintenance/replacement notes when judging the choices.
Check what each option emphasizes
For each answer, ask: Does this mainly talk about electricity, or about how often bulbs are replaced and what that costs? Eliminate any choice that doesn’t clearly tie LEDs to lower maintenance costs.
Look for a clear cause-and-effect chain
Among the remaining options, look for one that links: longer lifespan → fewer replacements → less labor/equipment for lane closures → lower maintenance costs.
Step-by-step Explanation
Identify the writing goal
The question states: "The student wants to emphasize how switching to LED streetlights can reduce maintenance costs."
So your answer must:
- Focus on maintenance (labor, equipment, lane closures, replacements), and
- Explain how LEDs lower those specific costs.
Anything that mainly talks about energy or electricity costs, or that doesn’t clearly connect LEDs to reduced maintenance, will not be the best choice.
Pull out the notes related to maintenance
From the notes, separate information about maintenance from information about energy:
Maintenance-related notes:
- A typical HPS bulb lasts about 24,000 hours.
- An LED streetlight can operate for up to 50,000 hours.
- Municipal crews must close lanes to change burned-out bulbs.
- Fewer replacements mean lower labor and equipment costs.
Energy-related note:
- LED fixtures use roughly 40% less electricity than HPS fixtures.
Since the task is to emphasize maintenance costs, the correct answer should mainly use the maintenance-related notes, not the electricity one.
Decide what the sentence needs to do
Using those maintenance notes, the best sentence should:
- Show that LEDs last much longer than HPS bulbs.
- Connect that longer lifespan to fewer replacements.
- Explain that fewer replacements mean less labor/equipment and therefore lower maintenance costs.
Look for an option that clearly links these ideas in one logical chain, not just listing facts or focusing on energy efficiency.
Evaluate each option against the goal
Now compare each answer choice to the task:
- One option talks mainly about using 40% less electricity; that is about energy, not maintenance costs.
- Another states that crews close lanes for bulb changes but does not explain how LEDs reduce this cost compared with HPS.
- A third option compares lifespans but concludes with energy efficiency, not reduced maintenance costs.
- The remaining option combines the longer LED lifespan with the idea that they need fewer replacements, and then explicitly connects this to saving money on labor and equipment for each street-lane closure.
The choice that does all of this is:
“LED streetlights, which can operate for up to 50,000 hours—more than twice the lifespan of a typical HPS bulb—would need to be replaced far less often, saving municipalities money on the labor and equipment required for each street-lane closure.”