Sound is audible to human beings only if the frequency is_____

Sound is audible to human beings only if the frequency is______.

单选题

2022-04-24 04:40

A、fewer than about 20 vibrations per second
B、more than about 20,000 vibrations per second
C、about in a range of 20 to 20,000 vibrations per second
D、120 vibrations per second

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正确答案

试题解析

细节题。文章第二段倒数第二句提到“The human ear is usually not sensitive to frequencies of fewer than 20 vibrations per second, or more than about 20,000 vibrations per second”，即“人的耳朵对每秒震动20次以下或2万次以上的声音不敏感”，因此C项正确。

标签：考研公共课外语

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