1. Create a use-case test plan. Including the specific class plans and invariant tests, for a use case from the A real Estate Inc. exercises in the previous chapters.for the real estate inc. problem in chapters 4 (exercises I,J,and K) 5 (exercises P and Q) and 6 (Exercises D): 1. perform a verification and validation walkthrough of th functional,structural and behavioral models to ensure that all between- model issues have been resolved. 2. Using the communication diagram and the CRUDE matix, create a package diagram of the problem domain layer. 3. perform a verification and validation walkthrough of the package diagram. 4. based on the analysis models that have been dreated and your current understanding of the girl's position, what design strategy would you recommen? why?