Following an excess supply of coffee beans, average retail coffee prices have fallen by 15% over the last six months.
What is the expected percentage change in the quantity of coffee demanded if the price elasticity of demand is -0.4?
−0.6%-0.6\%−0.6%
+0.6%+0.6\%+0.6%
−6%-6\%−6%
+6%+6\%+6%