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Draw an ERD for each of the following situations using Microsoft Visio , which can be found on the following link:1.A company has a number of employees. The attributes of EMPLOYEE include Employee_ID (identifier), Name, Address, and Birthdate. The company also has several projects. Attributes of PROJECT include Project_ID (identifier), Project_ Name, and Start_Date. Each employee may be assigned to one or more projects, or may not be assigned to a project. A project must have at least one employee assigned and may have any number of employees assigned. An employee's billing rate may vary by project, and the company wishes to record the applicable billing rate (Billing_ Rate) for each employee when assigned to a particular project. 2. A university has a large number of courses in its catalog. Attributes of COURSE include Course_ Number (identifier), Course_Name, and Units. Each course may have one or more different courses as prerequisites or may have no prerequisites. Similarly, a particular course may be a prerequisite for any number of courses or may not be prerequisite for any other course. 3.A laboratory has several chemists who work on one or more projects. Chemists also may usc certain kinds of equipment on each project. Attributes of CHEMIST include Employee_ID (identifier), Name, and Phone_No. Attributes of PROJECT include Project_ID (identifier) and Start_ Date. Attributes of EQUIPMENT include Serial_No and Cost. The organization wishes to record Assign_ Date-that is, the date when a given equipment item was assigned to a particular chemist working on a specified project. A chemist must be assigned to at least one project and one equipment item. A given equipment item need not be assigned, and a given project need not be assigned either a chemist or an equipment item. Provide good definitions for all of the relationships in this situation. 4. A college course may have one or more scheduled sections, or may not have a scheduled section. Attributes of COURSE include Course_ID, Course_Name, and Units. Attributes of SECTION include Section_Number and Semester_ID. Semester_ID is composed of two parts: Semester and Year. Section_Number is an integer (such as "1" or "2") that distinguishes one section from another for the same course but does not uniquely identifY a section. 5.A hospital has a large number of registered physicians. Attributes of PHYSICIAN include Physician_ID (the identifier) and Specialty. Patients are admitted to the hospital by physicians. Attributes of PATIENT include Patient_ID (the identifier) and Patient_Name. Any patient who is admitted must have exactly one admitting physician. A physician may optionally admit any