The Sensex opened with a positive gap of 119 points at 20,049. The index is now up 115 points at 20,045.HDFC has advanced 1.6% to Rs 2,917.Grasim and Ambuja Cements have moved up 1.3% each to Rs 3,660 and Rs 153, respectively.Bharti Airtel, BHEL, HDFC Bank, Cipla and ACC are up over 1% each.