DATABASE SYSTEM MODEL QUESTION

Draw an E/R diagram for the below mentioned database

you are going to design a database system for a transportation authority that manages regional transportation. In this region, each bus company has a unique name, a unique manager and a date of establishment. There will be an Employee entity which has: unique ID, name, lastname, salary, birthdate, age, address which is composed of street number, street name, city name and zipcode. An employee can either be (i) a manager with an experience attribute which denotes the number of years this person has been a manager, or (ii) a driver with a drivers license number and totals miles he has driven as a bus driver. Every bus is associated with a single driver and a driver only drives a single bus. Every employee can have multiple dependents. Dependents are denoted with a name, lastname and a relationship to the employee. Companies have multiple buses, and a bus belongs to a single company. For buses we have the following information: license plate number, make, model, capacity, last service date and the upcoming service date. There are stop locations, which have unique names and an address which is composed of a street number, street name, city name and zipcode. Bus lines have a unique line source and a unique line destination which are stop locations. Assume that buses do not stop in between. Each line can be associated with multiple buses and a bus can serve multiple lines.