We have the following relations:

Emp(E_id: integer, E_name: string, Age: integer, Salary: real)

Works(E_id: integer, Dep_id: integer, affectation: date)

Dept(Dep_id: integer, Dep_name: string, budget: real, Manager_id: integer)

a. What referential integrity constraints exist between these relations? b. What are the options for enforcing these constraints when a user attempts to delete a Dept tuple?