econ question

11. An important and useful result from mathematics says that a continuous real-valued function fon a closed and bounded subset S of some Euclidean space attains its maximum on the set 5. Give three examples to show that the conclusion of this result can be false if the following conditions are violated: (6 points total) (a) Continuity of f. (2 points) (b) Closedness of S. (2 points) (c) Boundedness of S. (2 points)