Problem 1: the process of buying glasses by a patient First, the patient requests an appointment at the Doctor's office to receive the prescription. The patient's contact information should be stored in a database. After having a prescription, the patient places the order for the glasses. The patient must provide the prescription and the frame choice when placing the order. The order information is stored in a database. The frame information is also stored in an independent database. Once the glasses have been made, a notification is sent to the patient from the store for a fitting and pay for the glasses, i.e, proceed with the purchase process. Finally, a purchase receipt is generated, and the payment information goes to the order database. Note: consider there is only one external entity for this system. Create the context and level 0 diagrams. Problem 2: accompanying dentist office system New patients complete a patient information form providing the following details: name, address, phone number, and medical history summary. This process is called collecting new patient information. The patient info is stored in a database. Making or changing an appointment starts when a patient calls to schedule a new appointment or postpone an existing one. The appointment file (database) is checked for an available time, generating a query. Based on the query result, the appointment is scheduled once a good time is found for the patient. The office's staff completes this process. Because appointments are often made in advance, a reminder postcard is usually mailed to each patient two weeks before the appointment by the office's staff. Note: consider there're two external entities, patients and staff. Create the context and level 0 diagrams