4. Why does gold, which is a relatively nonessential item, have a higher price than water, which 1s essental to life? 5. What are the two conditions that are met if a consumer 1s maximizing utility? 6.If a consumer is consuming a combination of goods and services on his budget line, has the consumer allocated his or her entire budget? Rob enjoys rock concerts and the opera. The table shows the marginal utility he gets from each activity. Rob has $100 a month to spend on concerts. A rock concert ticket is $20, and an opera ticket is $10. How many rock concerts and how many operas does he attend? Concerts Marginal utility Marginal utility per month from rock from operas concerts 90 120 80 90 60 60 ) : . 40 30 In problem 2, Rob's uncle gives him $30 20 20 to spend on concert tickets, so he now has $130. How many rock concerts and how many operas does he attend now that he has $130 to spend? In problem 2, if the price of a rock concert decreases to $10, how many rock concerts and operas will Rob attend