All the supply of peppermint oil is produced from mint plants grown in

All the supply of peppermint oil is produced from mint plants grown in one county by several competitive growers (the number of growers is not limited). The quality of land in the county varies greatly. Would you expect the long-run market supply curve to slope upward, downward, or remain constant? Why?

What will be an ideal response?

ANSWER

The long-run market supply curve will slope up because the growers have different costs. Those growers with poor-quality land have a higher average cost of production. The horizontal sum of the individual supply curves will slope up.