13. In perfect competition, each rm's individual demand curve for their product is a. Perfectly inelastic b. Perfectly elastic c. Downward sloping d. Upward sloping 14. If the demand curve for a product is vertical, we say that demand is a. perfectly elastic b. imperfectly elastic c. perfectly inelastic d. imperfectly inelastic 15. Economists refer to the ability to produce a good/service at a lower opportunity cost than another entity as possessing the a. Comparative Advantage b. Competitive Advantage c. Absolute Advantage d. Technological Advantage