[15] A couple borrowed $ 20000 to buy a cottage. The loan was amortized with 20 equal payments at the end of each half year at the interest rate : 2) = 5%. After making 10 payments, they were unable to pay the loan on time and missed 3 consecutive payments. The rest of the loan were refinanced and paid off at the end of 10 years with the same interest rate and same payment frequency. (The regular payments are rounded up to the nearest cent.) (a) [5] What is the regular payments before refinancing? (b) [5] What is the regular payments after refinancing? (c) [5] What is the concluding payment? (Round it to the nearest cent.)