Given the following information: Gross sales $1,500,000 Items purchased from out of state vendors $20,000 Items purchased under certificate of resale but used $5,000 Food sales included in gross sales $300,000 Sales to federal government included in gross $25,000 Sales to non-profit organizations included in gross $10,000 Sales to governments outside of Tennessee included in gross $12,000 Local tax rate Knox County Amount subject to single article tax $16,000 What is the single article tax?