(16 points) Charlotte is planning her short European vacation. She'll be travelling to different places in France and Germany in a span of 6 days. She has to decide how much time she wants to spend in each country. Suppose the utility derived by her from spending 9 days in Germany and spending f days in France is given by the utility function U (9, f) = 1119 + 2J7. How much time should she spend in Germany and France to maximize her utility? (Fractional numbers of days are allowed too) (4 points) What would be approximately the increase in the utility if Charlotte decides to stay in Europe for one extra day? Answer: * = 1/2