They are like that because they can't always be faulty and may have at least some spark of truth to this theory also as stated earlier a theory in scientific terms is just an observation so it can't really be turned down hence theory.
i think it's contact, dynamic, and regional
hope this helps
Answer:
Net force=120N-90N=30N
30N to the right
Explanation:
Primary succession occurs when a habitat that has completely destroyed reheals from complete scratch
On the other hand, secondary succession occurs when only a portion of the original ecosystem survives and is rebuilt from that