Answer:
William Crawford Gorgas, (born Oct. 3, 1854, Mobile, Ala., U.S.—died July 3, 1920, London, Eng.), U.S. Army surgeon who contributed greatly to the building of the Panama Canal by introducing mosquito control to prevent yellow fever and malaria.
Explanation:
B. Plantation owners started to prefer slave labor over indentured servants.
Explanation:
The Viking age ended when the raids stopped. ... It was no longer profitable or desirable to raid. The Vikings weren't conquered. Because there were fewer and fewer raids, to the rest of Europe they became, not Vikings, but Danes and Swedes and Norwegians and Icelanders and Greenlanders and Faroese and so on
B. The new middle class had leisure time and extra money
