Roquan, a single taxpayer, is an attorney and practices as a sole proprietor. This year, Roquan had net business income of $90,000 from his law practice (net of the associated for AGI self-employment tax deduction). His taxable income before the deduction for qualified business income is $100,000. (Leave no answer blank. Enter zero if applicable.) Required: a. Calculate Roquan's deduction for qualified business income. b. Assume the same facts provided above, except Roquan's taxable income before the deduction for qualified business income is $300,000. Parta Part b Deduction for qualified business income