c)
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)