1.Use of Entity Sets versus Attributes :- The entity set employee with attributes employee-name and telephone-number. It can easily be argued that a telephone is an entity in its own right with attributes telephone-number and location (the office where the telephone is located). Redefine the employee entity set as: The employee entity set with attribute employee-name The telephone entity set with attributes telephone-number and location The relationship set emp-telephone, which denotes the association between employees and the telephones that they have