5. For each of the following utility functions, (i) draw two or more indifference curves, (fi) find the marginal rate of substitution (MRS) as a function of z, and the utility level k, (in) determine whether MRS is diminishing- (a) "(21, 32) = 1 + In(32). (b) "(x1, 12) = 4x1 + 12. (e) (60) =n (d) "(3,m) = n+r]