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d)

4.7.3

4.7.4

4.7.5

Males and Females subclasses are complete. Mothers and Fathers are partial. All subclasses are disjoint.

4.7.6

4.7.7

4.7.8

We convert the ternary relationship Contracts into three binary relationships between a new entity set Contracts and existing entity sets.

4.7.9 a)

b)

c)

4.7.10

A self-association ParentOf for entity set people has multiplicity 0..2 at parent role end.

In a Library database, if a patron can loan at most 12 books, them multiplicity is 0..12.

For a FullTimeStudents entity set, a relationship of multiplicity 5..* must exist with Courses (A student must take at least 5 courses to be classified FullTime.