Oyster crackers are a complement for clam chowder. If the price of clam chowder falls, the quantity of clam chowder demandedfallsriseswhichraiseslowersthe demand for oyster crackers. Because of the change in the equilibrium quantity of oyster crackers, the demand for wheat flour by oyster crackers producersrisesfalls, causing the equilibrium price of wheat flour todecreaseincreaseThis means producers of bread facehigherlowerinput prices, and the supply of breaddecreasesincreasesThe resultingrisefallin the price of bread causes people to substituteaway from cereal and toward breadaway from bread and toward cereal, so the demand for cerealrisesfalls

Oyster crackers and clam chowder are complementary goods. If the price of clam chowder decreases, its quantity demanded will rise. As oyster crackers and clam chowder are complements, it means they are consumed together. So the demand for clam chowder will increase.

As the equilibrium quantity of oyster crackers increases, the producers will need more inputs to increase output. As a result, the demand for flour by the producers of crackers will increase.

An increase in the demand for flour would shift the demand curve for flour to the right. This rightward shift in the demand curve will cause the equilibrium price of flour to increase.

This increase in the flour price implies that the producers of bread will now face an increase in the price of inputs. This will increase the cost of producing bread.

This increase in the cost of production will cause the supply curve to move to the left. This leftward shift in the supply curve will reduce the equilibrium quantity of bread and equilibrium price.

As the price of bread falls, it will become cheaper. So the consumers will substitute bread for cereal. So the demand for bread will increase and that of cereal will fall.