At a location, rainwater runs off the cliff that is 15 meters high how is the face of the cliff most likely to change over time

not sure if this is what you'r looking for eubacteria and archaebacteria

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.