Please focus on question b and d.

A person borrowed $4000 on a bank credit card at a nominal rate of 24% per year, which is actually charged at a rate of 2% per month. what is the effective annual percentage rate (Effective APR) for the card? a) Assume that the person does not place any additional charges on the card and pays the bank $300 each month to pay off the loan. Let B(n) be the balance owed on the card after n months. Find explicit formula for B(n). How long will be required to pay off the debt? What is the total amount of money the person will have paid for the loan? b) IC c) d)