Tokyo stocks opened higher Friday, supported by bargain-hunting following sharp falls the previous day, with sentiment boosted by a new all-time high reached overnight on the U.S. Dow Jones index. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average rose 243.17 points, or 0.61 percent, from Thursday to 40,411.24. The broader Topix index was up 21.78 points, or 0.79 percent, at 2,772.59. On the top-tier Prime Market, gainers were led by mining, real estate, and air transportation shares. At 9 a.m., the U.S. dollar fetched 151.44-46 yen compared with 151.33-43 yen in New York a…