I need help with this database hw. Can someone help me with this? Thanks!

2) You are required to design a database system to assist with the administration of Post Office System. The following is the specification for the post office system: Each post office has a unique name, one or more telephone numbers, an address, and a manager who supervises the operation of the post office. Every manager has a designated room number. Each post office has a number of employees (Managers are also employees). Each employee has his/her SSN, name, address, and home telephone number recorded. Employees are either managers or officers. Every post office has only one manager. No two post offices have the same employees. Each officer has a designated desk number. Post offices have several departments, each responsible for different services. A department has its unique name,contact information, and office hours. Services provided by a department are identified by their inner service numbers within this department. The system should also record services names and fee rates. Customers go to post offices for different services, which are recorded as transactions. Each transaction has a unique transaction number. Transaction time and charge should also be kept. A customer's name and address are stored in the system. A transaction is finished by an officer and only one kind of service can be included in one transaction. Please create the ER diagram for the post office database system. Next, convert the ER-diagram into a set of tables. For each table, specify the candidate keys, primary key and the foreign keys