Which of the following statements is true? Multiple choice question. When the demand curve is vertical, changes in supply will tend to have a big impact on the equilibrium quantity. When the demand curve is horizontal, changes in supply will tend to have a big impact on the equilibrium price. When the supply curve is vertical, changes in demand will have no impact on the equilibrium quantity and a big impact on the equilibrium price. When the supply curve is horizontal, changes in demand will have no impact on the equilibrium quantity and a big impact on the equilibrium price. Need help? Review these concept resources