Tax Rates, latesha, a single taxpayer, had the following income and deductions for the year 2009.

Question

INCOME
Salary $60,000
Business Income $25,000
Intrest income(bonds)$10,000
Tax-exempt bond interes $ 5,000
________
TOTAL INCOME $100,000

DEDUCTIONS:
Business Expenses $ 9,500
Itemized deductions $20,000
Personal exemption $ 3,650
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TOTAL DEDUCTIONS $33,150

1. Compute Latesha's taxable income and federal tax liability for 2009.
2. Compute Latesha's marginal, average, and effective tax rate.
3. for tax planning purpose which of the three rates in part 2 is the most important?