Suppose that 6 years ago you borrowed $150,000 using a 30-year mortgage with an annual interest rate of 15% with monthly payments and compounding. The rate on 30-year mortgages has fallen to 13% per year with monthly payments and compounding. What is the net present value of refinancing if you assume that refinancing costs will be 4% of the new loan amount and you will pay off the new loan at the end of the 4th year?

Please show how to solve using a BA II plus calculator