Collecting information about an audience concerning their age range, gender, and ethnicity is part of

a demographic analysis.

Explanation:

The technique which is used for the understanding of the dynamics and dimension of the populations such as age, sex and ethnicity is called demographic analyses. It is important for the nation because it provides a proper understanding of the population and how the demographic factors like migration, death, and birth has affected it. Based on these information policies are made that best suit the area.

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