Supply and demand curves aren't fixed; they are constantly changing due to changes in the prices of other goods and changes in technology. An increase in demand means that consumers demand more of the good at any price. Similarly, an increase in supply means that producers supply more of the good at any price. For example, an increase in the price of gasoline is likely to decrease the demand for SUVs, because higher gas prices make driving an SUV more expensive. How do you think each of the following scenarios would affect the supply and demand for SUVs? Factor Affecting Demand or Supply Effect Price of sedans rises Increase demand for SUVs Price of tires rises