$.$ Spreadsheet Problem. Use Ch$7\_$Rent$\_$vs$\_$Own worksheet in Excel workbook provided with the book. Determine the after$-$tax IRR for owning versus renting in each of the five years with the following changes in the original assumptions in the spreadsheet:

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a$.$ The homeowner has a $15$ percent marginal tax rate instead of $28$ percent.

b$.$ Rents and property values will not increase over the five years.

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c$.$ The loan amount is $$105,000$ instead of $$120,000.$

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d$.$ The initial rent for year $1$ is $$15,000$ instead of $$12,000.$

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