original response of 150 to 200 words with in text citations and APA guidelines to 5 questions. a) Explain the unique characteristics of the four primary market structures. b) Explain why economic profits are zero in the long run in a monopolistically competitive market. c) What are the characteristics of a public good? d) Discuss the two ways that product differentiation affects the demand for a product. e) Describe at least five different forms of government intervention in the economy