8) Consider a market for a good consisting of only two consumers, say consumers A and B. The marginal benefit of consumer A from the Ist unit of the good is 5 TL/unit and from the 2nd unit is 3 TL/unit. The marginal benefit of consumer B from the Ist unit of the good is 6 TL/unit and from the 2nd unit is 4 TL/unit. a. (3pts. ) If the good is a non-rival good, what is the social marginal benefit (the marginal benefit according to the market demand) from the 2nd unit of the good? Explain. b. (3pts.) If the good is a rival good, what is the social marginal benefit (the marginal benefit according to the market demand) from the 2nd unit of the good? Explain