单项选择题
A. Between 19th and 20th Jefferson Street. B. Between 19th and 20th Jackson Street. C. Between 9th and 10th Jackson Street. D. Between 90th and 91th Jefferson Street.
A. To outline contrasting types of economic systems. B. To explain the science of economics. C. To argue for the superiority of one economic system. D. To compare barter and money-exchange markets.