How does specialization by workers benefit the firms employing them?

Explain the difference between a plurality and a majority in terms of choosing a candidate for a primary

What is the social order of the ancient river valley civilization of mesopotamia?

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.