Law of Supply and Demand
Not to put too fine a point on it, but the law of supply and demand is a bitch. Stripped of all details it basically states that the price of something is determined by the interaction of the quantities supplied and demanded. Therefore (1) an increase of the quantity demanded, holding the supply constant, will increase the price; (2) an increase in the quantity supplied, holding the demand constant, will decrease the price; (3) a decrease in the quantity demanded, holding the supply constant, will decrease …