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Zhejiang, as the heartland of the Jiangnan (Yangtze River Delta), remained the wealthiest area during the Six Dynasties (220 or 222–589), Sui, and Tang. After being incorporated into the Sui dynasty, its economic richness was used for the Sui dynasty's ambitions to expand north and south, particularly into Korea and Vietnam. The plan led the Sui dynasty to restore and expand the network which became the Grand Canal of China. The Canal regularly transported grains and resources from Zhejiang, through its metropolitan center Hangzhou (and its hinterland along both the Zhe River and the shores of Hangzhou Bay), and from Suzhou, and thence to the North China Plain. The débâcle of the Korean war led to Sui's overthrow by the Tang, who then presided over a centuries-long golden age for the country. Zhejiang was an important economic center of the empire's Jiangnan East Circuit and was considered particularly prosperous. Throughout the Tang dynasty, The Grand Canal had remained effective, transporting grains and material resources to North China plain and metropolitan centers of the empire. As the Tang Dynasty disintegrated, Zhejiang constituted most of the territory of the regional kingdom of Wuyue.

Which dynasty restored and expanded the network that became the Grand Canal of China?
Answer: the Sui dynasty
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Economic anthropology attempts to explain human economic behavior in its widest historic, geographic and cultural scope. It has a complex relationship with the discipline of economics, of which it is highly critical. Its origins as a sub-field of anthropology begin with the Polish-British founder of Anthropology, Bronislaw Malinowski, and his French compatriot, Marcel Mauss, on the nature of gift-giving exchange (or reciprocity) as an alternative to market exchange. Economic Anthropology remains, for the most part, focused upon exchange. The school of thought derived from Marx and known as Political Economy focuses on production, in contrast. Economic Anthropologists have abandoned the primitivist niche they were relegated to by economists, and have now turned to examine corporations, banks, and the global financial system from an anthropological perspective.

Economic anthropology covers what scope of human economic behavior?
Answer: historic, geographic and cultural
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When World War II started, tonnage levels at the port decreased and shipping activities were suspended; however, the war did provide economic benefits for the city. Petrochemical refineries and manufacturing plants were constructed along the ship channel because of the demand for petroleum and synthetic rubber products by the defense industry during the war. Ellington Field, initially built during World War I, was revitalized as an advanced training center for bombardiers and navigators. The Brown Shipbuilding Company was founded in 1942 to build ships for the U.S. Navy during World War II. Due to the boom in defense jobs, thousands of new workers migrated to the city, both blacks and whites competing for the higher-paying jobs. President Roosevelt had established a policy of non-discrimination for defense contractors, and blacks gained some opportunities, especially in shipbuilding, although not without resistance from whites and increasing social tensions that erupted into occasional violence. Economic gains of blacks who entered defense industries continued in the postwar years.

What world event caused this increased need for petrochemicals?
Answer:
World War II