answer to Q.1 in case of person having salary of 10000/- p.m., his taxable income without having any investment will be Rs. 120000/- and as per A.Y. 2008-2009 slab rate for individual person is Rs 110000/- i.e. his tax liability is on Rs. 10000/-i.e. 10000*10%=1000/-. we can divide it by 12 for calculating monthly deduction.