For 2013, Mario, a single individual with no dependents, receives income of $55,000 and incurs deductible expenses

Question:

For 2013, Mario, a single individual with no dependents, receives income of $55,000 and incurs deductible expenses of $9,000.
a. What is Mario's taxable income assuming that the expenses are deductions for AGI?
b. What is Mario's taxable income assuming that the expenses are miscellaneous itemized deductions from AGI?