Bob filed a single return for the 2010 tax year. His adjusted gross income is $80,000. He had net investment income of $9,000. In 2010, he had the following interest expenses:
Personal credit card interest: $4,000
Home mortgage interest: $8,000
Qualified mortgage insurance premiums: $1,500
Investment interest (on loans used to buy stocks): $10,000
What is the interest deduction for Bob for the 2010 tax year?