Which statement is true regarding the introduction of the steamboat

Bonus question: according to wikipedia, in chinese philosophy yin and yang "describes how seemingly opposite or contrary forces may actually be complementary, interconnected, and interdependent." what are some examples from the story that amy tan may have intentionally incorporated elements of yin and yang philosophy into this story? select 2.

An individual who is experiencing a prolonged period of stress would likely have levels of circulating than an individual who was not experiencing stress.

In exchange for land, a knight agrees to be a sort of sub-vassal to a vassal. this agreement was known as: investiture homage tyranny subinfeudation