A loan of $10,000 is to be repaid with level payments of $600 every three months until it is fully repaid. The interest rate on the loan is 6% per 4 months. After 2 years, the loan is refinanced at 4% per 4 months and is to be paid back over the next 3 years. What is the new quarterly payment amount? A. $520.40 B. $551.33 C. $581.47 D. $568.89