Answer:
The correct answer is 4.ecosystem.
Explanation:
An ecosystem is a system, that is, a set of elements that interact with each other, in which such elements are: physical environment, living beings and their interactions (predator-prey, parasite-host, competition, symbiosis, pollination, distribution of seeds , etc.) The interrelation between living beings (competition, parasitism, etc.) occurs through cycles of matter and energy flows on which the functioning of the entire ecosystem depends.
The end result is having two identical daughter cells.
Answer:
I would believe the mesosphere would be the most difficult layer to breathe. Troposphere is where we are, ov we can breathe here, stratosphere would be hard to breath in as well
