1. Explain the differences between a change in supply and a change in quantity supplied.

2. Indicate whether each of the following situations would shift the supply curve to the left, to the right, or not at all.

a. An increase in price of inputs b. An increase in the number of firms in the market c. An increase in the price of substitutes in production d. A decrease in the current price of the product e. A decrease in productivity f. A decrease in the expected future price of the product

3. If there is excess demand in a perfectly competitive market, does the government need to intervene to restore the equilibrium price and quantity? Why or why not?