3. (16 pts) Ricardo gets utility from peanut butter and celery. Ricardo only likes to eat 5 ounces of peanut butter (P) per two pieces of celery (C). Extra peanut butter without extra celery is of no value to Ricardo, just as extra celery is of no value without extra peanut butter. For the remaining parts of this problem put ounces of peanut butter (P) on the xaxis and pieces of celery (C) on the y-axis. a. What type of utility function represents Ricardo's preferences? Write down an expression for his utility. b. Draw one of Ricardo's indifference curves for peanut butter and celery. Indicate the coordinates for any signicant points on the indifference curve. Clearly indicate the direction in which his utility increases