2026年6月托福机经套卷(第1套)Listen to an Academic Talk / 24 道题

Listen to an Academic Talk / 2

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共用录音 1

What is the main topic of the talk?

AThe production process of two refrigerants

BThe life and career of an important chemist

CAn electronic device that led to medical innovations

DThe invention of a substance that has many practical uses

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正确答案：D

What problem was Roy Plunkett trying to solve?

ARefrigerants were unable to cool industrial systems.

BRefrigerants were unsafe to use.

CRefrigerants could not be stored effectively.

DRefrigerants could not be used in multiple applications.

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正确答案：B

What makes PTFE special?

AIt is available in gas and liquid form.

BIt can be used in medicines that cure poisoning.

CIt is unusually stable.

DIt can be mixed with TFE.

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正确答案：C

At the end of the talk, why does the speaker mention X-rays and penicillin?

ATo point out medical uses of PTFE

BTo emphasize the importance of research

CTo contrast PTFE with other advancements

DTo support a general point about many scientific discoveries

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正确答案：D