Question $2$: $[10$ Marks$]$

Assume your company is developing a generic digital camera online purchasing system that can

be sold to different camera stores. An initial analysis phase of the project has resulted in the

following informal description of relevant data for the system.

A store will be selling a variety of digital cameras and lenses. The digital cameras can have

following mutually exclusive optional features:

$1.$ An ability to replace lenses.