I need some help with these parts, my professor said I didn't do them right, not sure what I did wrong. This is an excel project.

Go to www.savewealth.com click on Tax Forms, Income Tax Rates, and then Married Filing Jointly to find the tax formula for Deb and Rusty. A column computing the yearly Federal Income Taxes.

7. Assume the rent is now $1000 a month and will increase by 3% each year. Compute their yearly federal income taxes (which are higher when renting because they don't have the deductions).

8. By renting they are saving a lot of money each year! They pay less for rent than a mortgage, and they don't pay property taxes (they do however pay more in income tax). Assume the extra money (include the $40,000 in savings as initial deposit) they have from renting versus buying is all invested at 10% a year, and every year their extra money is added to this account. column titled Extra Money. How much extra money do they have after 20 years?

9. Assume the house increases in value by 3% a year. Which option ends up with more money for Deb and Rusty to retire on assuming they sell the house after 20 years?