htra set exam they are giving answer tax liability is rs. 3,00,000 it's correct or wrong and suggest me which book i will refer for this question because i will challenge it. i think it's wrong answer

the tax liability on the total income before remuneration and interest rs.60000 of a professional firm is rs.1000000.after considering the dedication permissible u / s 40 ( b ), the tax payable by firm excluding education cess as will be. ....