Plz help me!! Does demography play a role in a population's growth rate? Explain

Ok, look...

Fertility, mortality, and migration all influence the size of a society's population. ... Demographers determine a population's natural growth rate by subtracting the crude death rate from the crude birth rate. The world's low‐growth nations tend to be more industrialized, such as the United States and Europe.

so the story tells of someone named kaushik choudhuri, but he does not narrate the story, a girl named hema does. hema tells the story in a second person point of view because you (the reader) are supposed to be the boy named kaushik.

here's an excerpt i found: "i was ushered into the fitting room, your mother watching approvingly as i took off my coat and sweater and tried on the bra."

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