What could the two extra trials show, according to Mr. Cole?
Listen to a Classroom Conversation · ELPAC Grades 9–10 listening. The correct answer, and the reasoning behind it.
A multiple-turn conversation between two speakers, followed by three questions.
Listen to the conversation between Mr. Cole and Hana about her lab report. Then answer the questions.
The Result That Did Not Fit
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Mr. Cole: Hana, I looked at your yeast data. Four of your five trials at forty degrees are close together, and then trial three is almost double the others. What happened there?
Hana: I am not sure. I was going to leave it off the graph so the pattern looks cleaner.
Mr. Cole: I would not do that. If you remove a result just because it does not match, a reader has no way of knowing whether the pattern is real or whether you only kept the results that fit it.
Hana: So I keep it in, even though it is probably a mistake?
Mr. Cole: You keep it in your data table, and you say what you think caused it. Did anything about that trial go differently?
Hana: Actually, yes. I opened a new packet of yeast for trial three. The other four all came from the same packet.
Mr. Cole: That is a real explanation, and it is worth a sentence in your report. Then run two more trials with the new packet tomorrow at lunch. If those come out high too, you have not found a mistake. You have found out something about the yeast.
The question
Choose the best answer.
What could the two extra trials show, according to Mr. Cole?
- That the higher result was caused by the new packet of yeast rather than by a mistake.Correct answer
- That forty degrees is the best temperature for yeast.
- That Hana measured the first four trials incorrectly.
- That the old packet of yeast had gone bad.
Why “That the higher result was caused by the new packet of yeast rather than by a mistake.” is correct
This is the hardest item in the set, because it asks the student to follow Mr. Cole's reasoning to its conclusion. If new trials with the new packet also come out high, the difference belongs to the yeast and not to an error, which is what he means by 'you have found out something about the yeast'. The question rewards understanding why an experiment is repeated, not only that it is.
Why the other answers are wrong
- That forty degrees is the best temperature for yeast. — The trials compare packets of yeast at the same temperature; they are not testing which temperature is best.
- That Hana measured the first four trials incorrectly. — The four matching trials are not under suspicion; the extra trials test the one that differed.
- That the old packet of yeast had gone bad. — The new packet produced the higher result, and nothing suggests the old one had gone bad.
Practice more of this
More listening practice for Grades 9–10, or see the ELPAC practice test for grades 9–10. For other grades, see free ELPAC practice tests by grade.
This is an independent study resource. It is not affiliated with, endorsed by, or connected to the California Department of Education or the official ELPAC program. All questions here are original practice material written to match the published task formats.