taxpayer is single and reports $$80,000$of gross revenue and $$50,000$ of ordinary and necessary business expenses, resulting in $$30,000$ of net profit on schedule C from a law practice. the taxpayer had no self$-$employed health deductions and $1/2$ of the self$-$employment tax is $$2,295.$ how much is the taxpayer's deduction for qualified business income $($QBI$)?$