In an economy that relies upon barter, a. trade does not require a double coincidence of wants. b. scarce resources are allocated just as easily as they are in economies that do not rely upon barter. c. there is no item in the economy that is widely accepted in exchange for goods and services. d. all of the above are correct.

In an economy that relies on barter, there is no item in the economy that is widely accepted in exchange for goods and services. Money is not used in a bartering system. Goods are exchanged for goods, and services are exchanged for services.

The business cycle is the periodic but irregular up-and-down movement in economic activity, measured by fluctuations in real gross domestic product (gdp) and other macroeconomic variables. a business cycle is typically characterized by four phases—recession, recovery, growth, and decline—that repeat themselves over time. economists note, however, that complete business cycles vary in length. the duration of business cycles can be anywhere from about two to twelve years, with most cycles averaging six years in length. some business analysts use the business cycle model and terminology to study and explain fluctuations in business inventory and other individual elements of corporate operations. but the term "business cycle" is still primarily associated with larger (industry-wide, regional, national, or even international) business trends.