6- (10pm) Consider a consumer with a utility function HUI, Y) = 4J3? + vri": 3} b) c} d) 0} Explain what marginal utility is. Compute marginal utilities ofX and Y. Evaluate whether marginal utilities ofX and Y are diminishing or not. Compute marginal rate of substitution. What is this consumer's marginal rate of substitution when she is consuming 4 units of X and 64 units an. Provide an intclpmtation {1me value of MRS you found in part {6}. Evaluate whether this consumer has diminishing marginal rate of substitution or not