(a) Identify the main entity types of the company.
(b) Identify the main relationship types between the entity types and determine the multiplicity constraints for each relationship
(c) Identify attributes and associate them with entity or relationship types.
(d) Determine candidate and primary key attributes for each (strong) entity type.
(e) Using your answers (a) to (d) create a single ER diagram. State any assumptions necessary to support your design.