Question: Make an IE Crow's Foot E-R diagram for the entities section and employee and the 1:N relationship between them. Suppose that a section/department does not require to have an employee, but that every EMPLOYEE is assigned to a DEPARTMENT. Include appropriate identifiers and attributes for each entity.

Give examples of binary 1:N relationships, other than those in the textbook, for (a) an optional-to-optional relationship, (b) an optional-to-mandatory relationship, (c) a mandatory-to-optional relationship, and (d) a mandatory-to-mandatory relationship. Illustrate your answer using IE Crow's Foot E-R diagrams.