The following is a description of some data requirements for a chain of pharmacies. Draw the appropriate entity-relationship diagram. Clearly show all cardinality constraints, cardinality limits, and existence dependencies. You may ignore the none-key attributes on the ERD to save your time but need to have the key attribute. (a) Pharmaceutical companies manufacture one or more drugs, and each drug is manufactured and marketed by exactly one pharmaceutical company. (b) Drugs are sold in pharmacies. Each pharmacy has a unique identification. Every pharmacy sells one or more drugs, but some pharmacies do not sell every drug. (c) Drug sales must be recorded by prescription, which are kept as a record by the pharmacy. A prescription clearly identifies the drug, physician, and patient, as well as the date filled. (d) Doctors prescribe drugs for patients. A doctor can prescribe one or more drugs for a patient and a patient can get one or more prescriptions, but a prescription is written by only a doctor e) Pharmaceutical companies may have long-term contracts with pharmacies and pharmacy can contract with zero, one, or more pharmaceutical companies. Each contract is uniquely identified by a contract number