You have just borrowed $10,000, which you will repay over 60 months at APR of 6%. The day you make your 24^th monthly payment, you pay an additional $1,700. After that, you continue to make your regular monthly payment. After the 24^th payment, how many more payments must you make to pay off the loan?

a.20.41

b.23.98

c.25.72

d.28.63

answer is c. please show work