You have two credit cards, credit card X with an interest rate nominal rate of 36% per year and a balance of $15,000 and the Z credit card with a rate of 30% annual nominal interest and a balance of $25,000. The interests are composed monthly in both cases. If you don't make any payments, what will your balance be? each card after 3 years? a) Calculate using effective interest rates annual. b) Confirm your results using monthly interest rates.