Which envoirnment changes are consider short term

Forest fires, earthquakes, and floods are all only short term changes

several tissues working together form an organ, and several organs together make up an organisms.

the group of cell that carries out special jobs are tissue.

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.