The frequency of the radiation in megahertz if extraterrestrial civilizations communicate at a wavelength of 21 cm .

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Chapter 27, Problem 25Q

(a)

To determine

The frequency of the radiation in megahertz if extraterrestrial civilizations communicate at a wavelength of 21 cm.

(b)

To determine

The merits of the suggestion provided in the answer of the above part (a).

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