2) Do you know that it costs a lot of money to get a 'UML' certificate? It could cost you thousands of riyals. Let's imagine we will develop a browser-based training system to help people prepare for such a certification exam. A user can request a quiz for the system. The system picks a set of questions from its database, and composes them together to make a quiz. It rates the user's answers, and gives hints if the user requests it. In addition to users, we also have tutors who provide questions and hints. And also examiners who must certify questions to make sure they are not too trivial, and that they are sensible. Make a USE CASE DIAGRAM to model this system. Work out some of your use cases. Since we don't have real stake holders here, you are free to fill in details you think is sensible for this example