Using the payoffs from the Free Trade Game, what is the present value of reducing tariffs?

Which of the following operational definitions of variables would have the properties of identity, magnitude, equal intervals, and a true zero?

A) IQ as measured by a standard IQ test B) driving speed measured in miles per hour C) political affiliation (classified as Democrat, Republican, or other) D) a person's body temperature measured on a Celsius scale

______ had the largest historical impact on the U.S. government’s becoming more involved in economic policy.

a. The Great Depression b. World War II c. The Civil War d. The war on poverty e. The war on drugs