In the light of the recent car-lite initiative, a small car rental company wants to record information concerning the rental and servicing of their small fleet of cars. Each car has a registration number, colour, engine number, comes with an initial mileage and has an acquired date recorded. Each car belongs to a particular model. Each model has a name which is typically used to reference the model. Each model is of a particular type and has an engine capacity, number of doors, number of seats. Each model belongs to a price band. Each price band has values for daily, weekly, weekend and monthly rates.

Customers of this rental car company are assigned a customer number. Name, address and contact values are recorded. Each customer also is given a rating. This value indicates to the staff as to whether this is a new customer (in which case the rating is 1), an easy or difficult customer. The cars are kept in road worthy conditions by regular servicing. A service is either for regular maintenance or repairs and replacement of parts or both. Service records include a service identifier, mileage and date. A car undergoes service maintenance during regular intervals. Some cars need servicing after having been driven 5000km or 10000km. Repairs would require the reason for the repairs to be recorded.

The company uses workshops for maintenance and repairs. Information recorded on workshops include workshop identifier, workshop name, address, contact and person in charge.

Many tasks are involved in the scheduled maintenance. These tasks are identified by a task name and description. Parts are used in repairs. Parts are identified by a part name and description. Cost of parts and cost of maintenance tasks depend on the workshop offering the service. As the company is very price sensitive, the cost of parts and cost of tasks charged by workshops is also required. Workshops carry out both types of servicing. The rental company would like to be able to track the different task(s) and all the different part(s) replaced during a single service session. Using the data requirements given above, draw an ER diagram to represent the data requirements of this car rental company. Provide the necessary:

(a) Entities, with their name, attributes and identifier

(b) Relationships with relationship names, max/min cardinalities