Two ways a population can increase is more births than deaths, and immigration to the area.
D) Selective cutting would result in more diverse regrowth.
3: because each vaccination has a different purpose. There's hundreds of different vaccines for different diseases. But 1 vaccine only works for a certain disease. Not ALL diseases.
Answer:
microorganisms capable of transforming atmospheric nitrogen into fixed nitrogen (inorganic compounds usable by plants). More than 90 percent of all nitrogen fixation is effected by these organisms, which thus play an important role in the nitrogen cycle.