Residual fuel oil stocks at key trading hub Singapore slipped to seven-week lows in the week to Sept. 6, official data showed on Thursday. Onshore fuel oil stocks STKRS-SIN dipped 2%to 19.45 million barrels (3.06 million metric tons), data from Enterprise Singapore showed. O/SING1 Weekly net imports rebounded 7% week-on-week at 592,000 tons, though this …