Ireally don’t know the top half so if you can’t answer all just answer them.

any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.