Radio Waves of 21-Cm Wavelength Originate from Which Component of the Interstellar

question 120

Multiple Choice

Radio waves of 21-cm wavelength originate from which component of the interstellar medium?

• A) Ionized atomic hydrogen
• B) Neutral atomic hydrogen
• C) Carbon monoxide,CO
• D) Molecular hydrogen,H₂

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Definitions:

Carbamates

A group of organic compounds used as insecticides, herbicides, or in pharmaceuticals, derived from carbamic acid.

Herbicides

Chemical substances used to control or kill unwanted plants (weeds), often used in agriculture and landscaping.

Systemic Chemicals

Chemical substances that are absorbed by an organism, affecting its entire system rather than a localized area, often used in plants to provide internal protection against pests.

Systemic Herbicides

Chemical substances used to kill unwanted plants, absorbed through the roots or foliage and transported throughout the plant to inhibit growth.