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Question 1 Read the case study carefully below: This case study concerns a library, where books are loaned to borrowers. The purpose of the database is to facilitate and record the activities of a library. A library is essentially composed of Borrower, Loan and Book. Each borrower has identification, an address, and a name. Each Loan is required to record the book, the issue date, who the Loan is issued to and the loan type which can be the number of days in a range from 0 (reference item only and not allowed on loan) to 28 days. Each Loan should also keep track of the number of renewals for a particular item on loan. 1) Identify the key entities in the case study and their relationships (5 marks). 2) Draw an ER diagram of the modelled entities and relationships at a conceptual level (5 marks). 3) Draw your ER model at logical level, make sure you identify attributes, keys and indicate the multiplicity of the relationship in the drawing (5 marks). 4) Explain the difference between conceptual, logical, and physical models (5 marks).