I used Check My Work to check my answers already, and it said all 3 of them (a,b and c) I got answers wrong. Please help me with it.

Check my work The Wagner Corporation has a $28 million bond obligation outstanding, which it is considering refunding. Though the bonds were Initially issued at 13 percent, the interest rates on similar issues have declined to 10.6 percent. The bonds were originally issued for 25 years and have 21 years remaining. The new issue would be for 21 years. There is a 8 percent call premium on the old issue. The underwriting cost on the new $28 million issue is $630,000, and the underwriting cost on the old issue was $480,000. The company is in a 34 percent tax bracket, and it will allow an overlap period of one month (1/12 of the year) Treasury bills currently yield 4 percent (Do not round intermediate calculations. Enter the answers in whole dollars, not in millions. Round the final answers to nearest whole dollar) ..Calculate the present value of total outflows Total outflows S771112 b. Calculate the present value of total inflows Total inflows $ 6,171067 c. Calculate the net present value Net present Value 5439995: d. Should the old issue be refunded with new debt