1. Although 3D modeling can describe part and assembly configuration in accurate detail, many parts or features are rarely included in a model until very late in the process if included at all. List four parts or features that fall into this category, and give reasons for omitting detail.
2. Component models of detail parts or assemblies can be obtained from suppliers and manufacturers. These models save the designer time and reduce the potential for error but can be difficult to use in a constraintbased model. Why? What advantage does the supplier gain from this service?