Exercise 2 - A UNIVERSITY A university consists of several faculties. Within each faculty there are several departments. Each department may run a number of courses. All teaching staff are attached to departments, each staff member belonging to a unique department. (Note: see how many meanings you can assign to this ambiguous sentence). Every course is composed of subcourses. Some subcourses are part of more than one course. Staff may teach on many subcourses and each subcourse may be taught by a number of staff. Draw an entity-relationship model for this example. Show both cardinalities and optionalities. Put a question mark where the degree is not clear from the text. Don't assume anything; rather, write a list of questions you would have to find answers to complete the model. Exercise 3 - STUDENTS AND COURSES (Similar to Exercise 2) Draw an entity-relationship diagram for the following scenario, stating any assumptions you find it necessary to make, and showing unknown cardinalities and optionalities using question marks on the relationship line. Show also the attributes explicitly mentioned in the scenario and underline any you consider suitable candidates for being primary keys. It is required to keep the following information on students, courses and subcourses. Each student has a name, identification number, home address, term address, and a number of qualifications for which the subject (e.g. maths), grade (e.g. C) and level (e.g. `A' level) are recorded. Each student is registered for one course where each course has a name (e.g. Information Systems) and an identification number. Record is kept of the number of students registered for each course.Each course is divided into subcourses where a subcourse may be part of more than one course. Information on subcourses includes the name, identification number and the number of students taking the course. Exercise 4 IT TRAINING COMPANY You are required to create a conceptual data model of the data requirements for a company that specializes in IT training. The company has 30 instructors and can handle up to 100 trainees per training session. The company offers five advanced technology courses, each of which is taught by a teaching team of two or more instructors. Each instructor is assigned to a maximum of two teaching teams or may be assigned to do research. Each trainee undertakes one advanced technology course per training session. (a) Identify the main entity types for the company. (b) Identify the main relationship types and specify the multiplicity for each relationship. State any assumptions you make about the data. (c) Using your answers for (a) and (b), draw a single ER diagram to represent the data requirements for the company.