Question 6 The discounted utility model (DUM) is the standard model used in economics to analyse intertemporal decisions. (a) Write down a general form for the DUM's discount function. explaining the concepts of discount factor. discount rate and positive time preferences. [6 marks] (b) in the DUM, what is the difference between the inferternporai utility function Ut(ct. 0m. Chit) and the instantaneous utility function U(Ct)? [6 marks] (c) Explain what it means to say that the DUM assumes constant discounting, consumption independence and constant instantaneous utility. [6 marks] (d) Using the Smaller-Sooner Larger-Later (SSLL) paradigm. explain what it means to say that the DUM produces time-consistent preferences. [7 marks] is) Explain how time-inconsistent preferences may arise as a result of a violation of the constant discounting assumption, or may occur if the instantaneous utility function is not constant. [8 marks]