You just charged $600 to your credit card. You can pay back $50 each month and the interest is 12% per year. a. How long will it take to pay off your balance? b. If the interest rate increases to 18% per year, will you need a longer or shorter time to pay off the balance? (Round all answers to two decimal places. Do NOT include any symbols or punctuation marks (e.gu $ %, commas, etc.)) Blank # 1 AN Blank # 2 A/