if you could show the formulas, that would be great!

North Star Company is considering whether or not to refund a $115 million, 5.75% coupon, 25-year bond issue that was sold 9 years ago. It is amortizing $5.5 million of flotation costs on the 5.75% bonds over the issue's 25-year life. Star's investment bankers have indicated that the company could sell a new 16-year issue at an interest rate of 4% in today's market. Neither they nor Star's management anticipate that interest rates will fall below 4% any time soon, but there is a chance that interest rates will increase. A call premium of 5% would be required to retire the old bonds, and flotation costs on the new issue would amount to $4.6 million. Star's marginal federal-plus-state tax rate is 40 percent. a. Perform a complete bond refunding analysis. What is the bond refunding's NPV? Initial investment outlay to refund old issue: Call premium on old issue = After-tax call premium = New flotation cost = Old flotation costs already expensed = Remaining flotation costs to expense = Tax savings from old flotation costs = Total investment outlay = Annual Flotation Cost Tax Effects: Annual tax savings on new flotation = Tax savings lost on old flotation = Total amortization tax effects = Annual interest savings due to refunding: Annual after tax interest on old bond = Annual after tax interest on new bond = Net after tax interest savings = After-tax cost of new debt = NPV of refunding decision = North Star Company is considering whether or not to refund a $115 million, 5.75% coupon, 25-year bond issue that was sold 9 years ago. It is amortizing $5.5 million of flotation costs on the 5.75% bonds over the issue's 25-year life. Star's investment bankers have indicated that the company could sell a new 16-year issue at an interest rate of 4% in today's market. Neither they nor Star's management anticipate that interest rates will fall below 4% any time soon, but there is a chance that interest rates will increase. A call premium of 5% would be required to retire the old bonds, and flotation costs on the new issue would amount to $4.6 million. Star's marginal federal-plus-state tax rate is 40 percent. a. Perform a complete bond refunding analysis. What is the bond refunding's NPV? Initial investment outlay to refund old issue: Call premium on old issue = After-tax call premium = New flotation cost = Old flotation costs already expensed = Remaining flotation costs to expense = Tax savings from old flotation costs = Total investment outlay = Annual Flotation Cost Tax Effects: Annual tax savings on new flotation = Tax savings lost on old flotation = Total amortization tax effects = Annual interest savings due to refunding: Annual after tax interest on old bond = Annual after tax interest on new bond = Net after tax interest savings = After-tax cost of new debt = NPV of refunding decision =