A travel/tour company provides a broad range of tours and travel services with discounts for their members. A member may be an individual member or a company member that allows the company's employees to use the services. An individual member will pay his/her own travel expenses, a company employee will be paid for by his/her company. The payment will be charged by credit cards.
The travel company offers the following categories of services:
Use an Enhanced ER Diagram (EERD) to design a database to track a member using their services. The EERD must include some EERD notations such as superclass, subclass, categories, and other constraints. You only need to include key attributes for the entities (such as Air Travel and so on) and relationships to reduce complexity of your design. You don't need to identify attributes associated with Air_Travel and other entities.
Please state clearly any assumptions you make and your design rationale. You may use any graphical tools to draw your EERD or you can use hand-writing to clearly show your EERD.