monopolistic competition 독점적 경쟁 1. characteristics of monopolistic competition 독점적 경쟁의 특징 2. monopolistic competition in the short run 단기 독점적 경쟁 3. monopolistic competition in the long run 장기 독점적 경쟁 4. monopolistic competition & welfare 독점적 경쟁과 복지 5. advertising 광고