When the birth rate is equal to each woman producing exactly enough offspring to replace herself and her offspring's father, and the birth rate is sustained for a generation, then .

Explanation:

When the birth rate is equal to each woman producing exactly enough offspring to replace herself and her offspring's father, and the birth rate is sustained for a generation, then there will be no increase in population so the net population growth will be zero.

Population of species is defined as the number of individuals of a given species.

For example, if their were 50 individuals in a population and a woman out of them mates with a man and produces one offspring to replace her and one offspring to replace her offspring's father, and then both of them die.

So the intrinsic rate of population growth = No. of birth -no. of death

                                  Growth rate

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