The major difference was the decision on actually becoming a knight. For people who could become knights (because their father was one), it was optional to become a knight. For a samuari, this option didn't come into play - they had to become one if their father was a samurai.
Air pollution is the biggest environmental problem in China. I believe this is the right answer :)<span />
Answer: They were able to successfully regulate water levels and prevented flooding during major storms.
Explanation:
This is called cell division.
Cell division is the mechanism by which DNA is passed from one generation of cells to the next and ultimately, from parent organisms to their offspring.
