If the price of walnuts rises, many people would switch from consuming walnuts to consuming pecans. but if the price of salt rises, people would have difficulty purchasing something to use in its place. these examples illustrate the importance of a. the availability of close substitutes in determining the price elasticity of demand. b. a necessity versus a luxury in determining the price elasticity of demand. c. the definition of a market in determining the price elasticity of demand. d. the time horizon in determining the price elasticity of demand.

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.

Ithink its 1e100 but im not sure.