South Korean stocks rose nearly 1 percent to top 2,500 points Friday as foreign investors returned to net buyers for the first time in 11 sessions. The local currency fell to surpass 1,400 won against the US dollar. The benchmark Korea Composite Stock Price Index gained 20.61 points, or 0.83 percent, to close at 2,501.24. It is the first time that the main index topped the 2,500-point threshold since it ended at 2,531.66 on Nov. 11. Trade volume was moderate at 534.9 million shares worth 7.8 tri