(a)[8]
Using diagram(s), briefly explain how the reason for a movement along the demand curve differs from the reason for a shift in the demand curve and assess the effect on the demand for one good of price changes in other goods.
(b)[12]
Assess whether knowledge of income elasticity of demand or price elasticity of demand for its product is more useful to a business trying to raise the total expenditure on its product during a period of economic growth.