Assume the existence of a BankAccount class. Define a derived class, SavingsAccount that contains two instance variables: the first a double, named interestRate, and the second an integer named interestType. The value of the type variable can be 1 for simple interest and 2 for compound interest. There is also a constructor that accepts two parameters : a double that is used to initialize the interestRate variable , and a string that you may assume will contain either “Simple”, or “Compound”, and which should be used to initialize the type variable appropriately. There should also be a pair of functions getInterestRate and getInterestType that return the values of the corresponding data members (as double and int respectively).