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CHAPTER 7: RELATIONAL DATABASE DESIGN BY ER- AND EER-TO-RELATIONAL MAPPINGAnswers to Selected Exercises7.3 Try to map the relational schema of Figure 6.12 into an ER schema. This is part ofa process known as reverse engineering, where a conceptual schema is created foran existing implemented database. State any assumptions you make.Answer:Note: We represented BOOK_AUTHORS as a multi-valued attribute of BOOK in theaboveER diagram. Alternatively, it can be represented as a weak entity type.7.4 Figure 7.7 shows an ER schema for a database that may be used to keep track oftransport ships and their locations for maritime authorities. Map this schema intoa relational schema, and specify all primary keys and foreign keys.Answer:SHIPSNAME OWNER TYPE PNAME