It has all to do with Pangaea, when we where all one continent. when we separated the monkeys went with the continent, understand? <span />
Irrigation of crops led to salinization of the soil, Sumer was located on a flat plain that provided no natural barriers to invasion, and the land became too swampy to grow adequate crops.
Answer:
a) Japan formed an alliance with China to protect east asian economic interests
Explanation: