Tokyo, March 5 (Jiji Press)–Japan’s Nikkei 225 stock average jumped over 2,300 points Thursday morning, rallying from a 4,600-point loss in its three-day slump through Wednesday. The key index reached 56,619.98 at 9:40 a.m., advancing 2,374.44 points, or 4.38 pct, from Wednesday’s