Answer :
Answer: 3. percentage change in quantity demanded of a product in response to the percentage change in the price of the good.
Explanation:
As you well know, prices of goods can usually have an effect on the demand for a good. This phenomenon is known as Price Elasticity of Demand.
Price Elasticity of Demand is simply a measure of how people respond to a change in the price of a good. Do they buy it more or less or does the demand not change at all.
It is calculated by dividing the percentage change in quantity demanded of a product by the percentage change in the price of the good.