Figure 2 for your reference as below, please see it for help to do (a)-(d), Thanks!!!!!!!!!!!!!!!!!!!

The relational representation in Figure 2 does not include all of the constraints required to model this part of the engineering company. Show how the following constraints can be represented in the model: (a) The estimated finish date for a project has to be later than the start date. (4 marks) (b) A member of staff can only be a manager if of grade 3, 4 or 5. (6 marks) (c) Each member of staff must be either a member of a project team or a manager of a team. (6 marks) (d) No members of staff can be both a manager of any project team and a member of any project team. (4 marks) model Engineering Company domains StaffNumbers = {S0001...89999 Projectlds = {P0001...P9999; Machinelds = {M000...M999} Names = String Descriptions = String Grades = {1...5) Dates = standard dates relation Staff StaffNo: StaffNumbers Name: Names Grade: Grades AppointmentDate: Dates primary key StaffNo relation Company Project Projectld: Projectlds StartDate: Dates EstimatedFinishDate: Dates Manager: StaffNumbers primary key Projectld alternate key Manager foreign key Manager references Staff constraint ((project Company Project over Projectld) difference (project WorksOn over Projectld)) is empty constraint ((project Company Project over Projectld) difference (project Machine over Projectid)) is empty relation WorksOn Projectld: Projectlds StaffNo: StaffNumbers primary key (Projectid, StaffNo) foreign key Projectld references Company Project foreign key StaffNo references Staff relation Machine Machineld: Machinelds Description: Descriptions DateOfLastService: Dates Projectld: Projectlds primary key Machineld foreign key Projectld references Company Project relation Machine Training Machineld: Machinelds StaffNo: StaffNumbers Date Of Training: Dates primary key (Machineld, StaffNo) foreign key Machineld references Machine foreign key StaffNo references Staff Figure 2 Part of a relational representation of an engineering company