2. A Canonical Utility Function. Consider the utility function 1(C)= where c denotes consumption of some arbitrary good and o (the Greek letter "sigma") is known as the "curvature parameter" because its value governs how curved the utility function is. In the following, restrict your attention to the region c >0 (because "negative consumption" is an ill-defined concept). The parameter o is treated as a constant. a. Plot the utility function for o =0. Does this utility function display diminishing marginal utility? Is marginal utility ever negative for this utility function? b. Plot the utility function for =1/2. Does this utility function display diminishing marginal utility? Is marginal utility ever negative for this utility function