Question: Using the Crow's Foot notation, create an ERD that can be implemented for a medical clinic using the following business rules:

• A patient can make many appointments with one or more doctors in the clinic, and a doctor can accept appointments with many patients. However, each appointment is made with only one doctor and one patient.

• Emergency cases do not require an appointment. However, for appointment management purposes, an emergency is entered in the appointment book as "unscheduled."

• If kept, an appointment yields a visit with the doctor specified in the appointment. The visit yields a diagnosis and, when appropriate, treatment.

• With each visit, the patient's records are updated to provide a medical history.

• Each patient visit creates a bill. Each patient visit is billed by one doctor, and each doctor can bill many patients.

• Each bill must be paid. However, a bill may be paid in many installments, and a payment may cover more than one bill.

• A patient may pay the bill directly, or the bill may be the basis for a claim submitted to an insurance company.

• If the bill is paid by an insurance company, the deductible is submitted to the patient for payment.