18.7 (SavingsAccount Class) Create a SavingsAccount class. Use a static data member annual- InterestRate to store the annual interest rate for each of the savers. Each member of the class con- tains a private data member savingsBalance indicating the amount the saver currently has on deposit. Provide member function calculateMonthlylnterest that calculates the monthly interest by multiplying the balance by annuallnterestRate divided by 12; this interest should be added to savingsBalance. Provide a static member function modifylnterestRate that sets the static an- nuallnterestRate to a new value. Write a driver program to test class SavingsAccount. Instantiate two different objects of class SavingsAccount, saverl and saver2, with balances of $2000.00 and $3000.00, respectively. Set the annuallnterestRate to 3 percent. Then calculate the monthly in- terest and print the new balances for each of the savers. Then set the annuallnterestRate to 4 per- cent, calculate the next month's interest and print the new balances for each of the savers. 18.7 (SavingsAccount Class) Create a SavingsAccount class. Use a static data member annual- InterestRate to store the annual interest rate for each of the savers. Each member of the class con- tains a private data member savingsBalance indicating the amount the saver currently has on deposit. Provide member function calculateMonthlylnterest that calculates the monthly interest by multiplying the balance by annuallnterestRate divided by 12; this interest should be added to savingsBalance. Provide a static member function modifylnterestRate that sets the static an- nuallnterestRate to a new value. Write a driver program to test class SavingsAccount. Instantiate two different objects of class SavingsAccount, saverl and saver2, with balances of $2000.00 and $3000.00, respectively. Set the annuallnterestRate to 3 percent. Then calculate the monthly in- terest and print the new balances for each of the savers. Then set the annuallnterestRate to 4 per- cent, calculate the next month's interest and print the new balances for each of the savers