Question

modem is a device used for rectification or modulation and demodulation​

Answer 1

yes this statement is right

Answer 2

The modem is a device used for rectification or modulation and demodulation

• The modem is mainly defined as an acronym for modulator-demodulator.
• It is a device that makes it conceivable for computers to interconnect with one another without being directly linked to each other.  
• An illustration of a modem is the device that is used for a computer to interconnect with a satellite.

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