Please answer the following questions about ER diagram and translation to the relational model.
a) When translating an ER diagram to the relational model, do all relationships end up as relations in the relational model? Explain your answer.
b) What are the three categories of relationships in ER diagrams?
c) What distinguishes relationships in "roles" from all other relationships in an ER diagram?
d) When ISAs in the ER diagram are translated to the relation model, what types of translations are possible?
e) When an attribute to a relationship needs to be multiple valued, i.e. a list of values, to match the natural language description of a database, how must the ER diagram be restructured?