Tokyo stocks opened mixed Wednesday as selling following an overnight decline on Wall Street was offset by buying of electrical appliance issues after Sony Group Corp. raised its net profit forecast for the year through March. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 29.03 points, or 0.10 percent, from Tuesday to 27,649.89. The broader Topix index was up 3.15 points, or 0.16 percent, at 1,941.65. On the top-tier Prime Market, decliners were led by electric power and gas, pharmaceutical and precision instrument issues, while iron and steel, electric appliance …