Mumbai, April 22 : The BSE Sensex on Friday tanked 714.53 points to close at 57,197.15 on profit booking by local operators. The Nifty of the National Stock Exchange (NSE) too slipped 220.65 points at 17,171.95. The Sensex registered the day’s high and low at 57,689.86 and 57,134.72 points respectively. The Nifty recorded the day’s high and low at 17,315.30 and 17,149.20 respectively. NV MR