a) Give the identifier (basic attributes) of each entity set. b) Express the data requirements that meet the relationships given in the ER diagram above in natural language and from the perspective of a field expert. c) Make schema definitions in SQL DDL. d) Is there a semantic difference between the ER diagram given above and the one below? if so, what is it?

Consider the ER diagram given above. Assume that a course may or may not use a textbook; furthermore, a text by definition can be a book used in a course. A course may not use more than five books. Instructors teach from two to four courses. An instructor may adopt one or more texts for a course. Supply (min, max) constraints on this diagram. TEXT