Design and implement the following classes: a. Consider the abstract base class Transaction defined in the previous exercise. Derive a class named Purchase from the Transaction class. This class...

Design and implement the following classes:

a. Consider the abstract base class Transaction defined in the previous exercise. Derive a class named Purchase from the Transaction class. This class should contain various details required for making a purchase from an organization’s point of view. It should also have the functionality for calculating the purchase amount.

b. Derive two classes CashPurchase and CreditPurchase from the base class Purchase . The CashPurchase class should have a member variable for storing the discount received from the retailer. The class CreditPurchase should have a member variable storing the date of payment.

c. Derive two classes CashSale and CreditSale . The CashSale class should have a member variable for storing the discount paid to the customer. The class CreditSale should have a member variable for storing the date of receipt of payment from the customer.