[spunkets]

"Our discussion hinges on whether the birthrate and lifespan are pertinent information."

Only the birthrate matters, because you're given the 24K fixed population. Supercat's answer is right in #20.

[supercat]

Only the birthrate matters, because you're given the 24K fixed population. Supercat's answer is right in #20.

There are three variables supplied: average birth rate per individual, average lifespan, and rate of population growth (which is specified as none). The supplied values for these variables are contradictory.