This is a correct answer to the following question about Demand curve. Yes or no?
Answer: Demand curves are used to estimate behaviors in competitive markets , and are often combined with supply curves to estimate the equilibrium price (the price at which sellers together are willing to sell the same amount as buyers together are willing to buy, also known as market clearing price) and the equilibrium quantity (the amount of that good or service that will be produced and bought without surplus/excess supply or shortage/excess demand) of that market.
Question: when does a demand curve shift?
