S. 144 : Best judgment assessment-Failure to produce vouchers and books of account-Not owning the Trucks-Estimation of profit-Failure to produce books of account-Assessing officer estimating at 12 Per Cent on gross receipts-CIT(A) reducing to 5 Per Cent-Tribunal applied 2.5 Per Cent of net profit rate on gross receipts. [S. 44AB, 143(3), 145(3)]