Question 3(25pts) : A graft copolymer was synthesized using a polyisoprene backbone with Mn =30kg/mol by grafting poly(lactic acid) polymer chains with an average degree of polymerization of 250 to the polyisoprene backbone. With this information answer the following questions. a) Draw the repeat units of the backbone and graft polymer. What are the molecular weights of the repeat units? b) How many repeat units are present in the polyisoprene backbone? c) If on average, one poly(lactic acid) chain adds per 50 repeat units of polyisoprene, what is the Mn of the resulting graft copolymer? d) If the dispersity of the polyisoprene backbone was 1.03 and the dispersity of the poly(lactic acid) grafts were 1.10, what is the expected dispersity of the graft polymer