Oil prices slipped further on Friday, heading for a weekly loss of more than 6 percent, after a report that Washington has granted several countries waivers on sanctions on Tehran, allowing them to continue to import Iranian crude.  Benchmark crude oil LCOc1 was down 20 cents a barrel at $72.69 by 0900 GMT. The contract has fallen 12 percent since the beginning of October. U.S. light crude CLc1 was 25 cents lower at $63.44, down more than 13 percent since hitting four-year highs a month ago. Global markets, including oil, were lifted earlier on Friday by hopes that the trade dispute between the world’s two biggest economies could be resolved soon. But sentiment turned […]