Phase of accelerated growth of logistic growth curve is . . . . . . .

In a population,if the number of post-reproductive age organisms is more than the reproductive age organisms,what will be the result for the population?

In which phase is the human population after the $17^{th}$ century?

$I.$ Populations evolve to maximize their reproductive fitness,also called Darwinian reproductive fitness (higher $r$ value),in the habitat in which they live.
$II.$ The population growth rate $r$ is inversely related to generation time.
$III.$ The housefly,which has a short life span and produces a large number of eggs,could be considered as a '$K$' selected species.
$IV.$ Under a particular set of selection pressures,organisms evolve towards the most efficient reproductive strategies.
$V.$ Life history traits of organisms have evolved in relation to the constraints imposed by biotic and abiotic factors in their habitat.
Select the combination of correct statements.

Which of the following formulas can be used to measure exponential growth?

Populations evolve to maximize their reproductive fitness,also called Darwinian fitness,with: