I Want Draw ER diagram & Map for ERD to Relation Model according for these requirements

Spa database management system: A system in which data of Services, data of Employee, data of customer would be saved and will be interrelation with each other. Services data: Service Number, Service Type, Price, state of service. Employee data: Employee Name, unique Id, Address, number, multiple certificates. Customer data: Customer number, Name (First, Last name), Address, date of Birth. Each service has the manager that mange only one service. The manager is also Employee, keep track working start date for each manager. A service paid by only one customer and Keep track of total bill of a customer that can pay for many services. a. Create a complete ER diagram for the previous scenario (Including all the requirements). b. Map your ERD to Relation Model according to what you have learned in theory lectures