When consumer spending is broken down into the major categories of goods and services, the largest single category is spending on transportation

An economic variable that is measured per unit of time, such as spending per year, is known as a: a. stock variable

b. periodic variable. c. dummy variable. d. flow variable. e. controlled variable.

The economist who advocated a single tax on land was:

A. Adam Smith. B. John Maynard Keynes. C. Henry George. D. Milton Friedman.