Complete the following tasks:
a. Develop a use case diagram for a convenience food store. Include an actor representing the store manager and use cases for orderItem(), stockItem(), and sellItem().
b. Add more use cases to the diagram you created in Exercise 1a. Include two generalizations for stockItem() called stockPerishable() and stockNonPerishable(). Also include an extension to sellItem() called checkCredit() for cases in which a customer purchases items using a credit card.
c. Add a customer actor to the use case diagram you created in Exercise 1b. Show that the customer participates in sellItem(), but not in orderItem() or stockItem().