Create a set of the use cases for the process of buying glasses from the viewpoint of a patient, but do not bother to identify the steps within each use case. (Just complete the informations at the top of the use case form.) The first step is to see an eye doctor who will give you a prescription. Once you have a prescription, you go to a glass store, where you select your frames and place the order for your glasses. Once the glasses have been made, you return to the store for a fitting and pay for the glasses.Please tell me the Preconditions,Normal Course,Post Condition and Exceptions for this example.