What is the central idea of "Psst ... Hey, You" that is supported by the other articles?

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What is the central idea of "Psst ... Hey, You" that is supported by the other articles?  Sound technology continues to evolve. Modern inventors must compete for recognition. Directional speakers are useful in commercial business. Advances in technology are prohibitively expensive.

Sound technology continues to evolve.

Explanation:

In "Psst ... Hey, You" we can see how music can be a factor in advancing technology and science as a whole. That's because within the article, we can read several situations where sound technology can interfere in different situations, from advertisements to technological equipment used in wars.

Sound technology is in a constant process of evolution, and each evolution allows a great scientific advance that can have several consequences in our lives.

the publisher is the publishing date is the author is

united states of america . . 1942 . . t. s. eliot

houghton mifflin company . . 2002 . . gregory stock

houghton mifflin company . . 1942 . . t. s. eliot

houghton mifflin company . . 2002 . . robert overholtzer