The number of events that occur in a given population in a given period of time is a RATE.
They can only estimate because- 1) they can't estimate how fast they can brood 2) they don't know if their predators will reproduce fast 3) they don't know if people will stop killing and destroying habitats 4) They don't know where all the species are, they might have escaped into other places fit for them to live
It would be A, they both have different properties, as they say it, different functions.
No one is for females and one is for male chromosomes
