The field of economics that combines the study the psychology of human behavior and economic issues is

Monetary freedom refers to:

a. the ability to create and operate an enterprise easily. b. the absence of tariff and non-tariff barriers that affect imports of goods. c. the tax burden and overall tax revenue of the government. d. price stability with an assessment of price control. e. the free flow of foreign capital.

What are the sources of increasing returns and economies of scale of the recent increase in trend rate productivity experienced in the U.S.?

Please provide the best answer for the statement.