A taxpayer has $20,000 in meal expenses during the year for his sole proprietorship. $5,000 of these are for regular business meals during work-related travel. $10,000 are for meals from restaurants. $5,000 are for meals served on the business premises as de minimus fringe benefits and for the convenience of the employer. How much of the $20,000 is eligible for treatment as an expense against business income for TY2023