Copper was the resource that was
so valuable that it aided the growth of kingdoms by becoming a form of currency
and a major source of political power. The answer is letter C. Copper used was
10000 years old and discovered at the Middle East in 9000BC.
Federalism is a mixed or compound mode of government that combines a general government with regional governments in a single political system. Its distinctive feature, first embodied in the Constitution of the United States of 1789, is a relationship of parity between the two levels of government established.
Malaria
Dr. John Gorrie practiced medicine in Florida. He experimented with ways to prevent the spread of malaria. The summer of 1841 was a particularly bad summer for malaria infection. People had not yet realized that malaria was spread by mosquitoes. (That discovery didn't occur till the 1890s.) Dr. Gorrie, noting that malaria was unlikely to occur in colder climates, thought that perhaps cooling the air in the sick rooms of his patients could help them. He started with the idea of using a fan to blow air across a bucket of ice. A rudimentary beginning to air cooling and refrigeration ... but as they say, the rest is history!
