This question was asked in my homework, and I cannot recreate the numbers they show to be correct. Help, please! Please show work. I need to understand how this is calculated so I can put in a spreadsheet. Thanks Very Much!

Problem 9-7 (book/static) Question Help A high-speed electronic assembly machine was purchased two years ago for $50,000. At the present time, it can be sold for $25,000 and replaced by a newer model having a purchase price of $42,500; or it can be kept in service for a maximum of one more year. The new assembly machine, if purchased, has a useful life of not more than two years. f the before-tax MARR is 15%, when should the old assembly machine be replaced? Use the following data table for your analysis Challenger Defender Year Market Value O&M Costs Market Value $25,000 17,000 O&M Costs $42,500 31,000 25,000 $14,000 $10,000 12,500 Click the icon to view the interest and annuity table for discrete compounding when the MARR is 15% per year The minimum EUAC value of the challenger is $ 25676 (Round to the nearest dollar.) The marginal cost of keeping the defender in service for one more year is S 25750. (Round to the nearest dollar.) The old assembly machine should be replaced immediately Problem 9-7 (book/static) Question Help A high-speed electronic assembly machine was purchased two years ago for $50,000. At the present time, it can be sold for $25,000 and replaced by a newer model having a purchase price of $42,500; or it can be kept in service for a maximum of one more year. The new assembly machine, if purchased, has a useful life of not more than two years. f the before-tax MARR is 15%, when should the old assembly machine be replaced? Use the following data table for your analysis Challenger Defender Year Market Value O&M Costs Market Value $25,000 17,000 O&M Costs $42,500 31,000 25,000 $14,000 $10,000 12,500 Click the icon to view the interest and annuity table for discrete compounding when the MARR is 15% per year The minimum EUAC value of the challenger is $ 25676 (Round to the nearest dollar.) The marginal cost of keeping the defender in service for one more year is S 25750. (Round to the nearest dollar.) The old assembly machine should be replaced immediately