LONDON: Crude oil prices slumped close to $40 a barrel in trading on Friday as the United States lost a stunning half a million jobs in November, raising prospects of a steep drop in energy demand.In London, Brent North Sea crude hit $40.72 a barrel, the lowest level since the start of 2005. Light sweet crude for January slid to $42.00 in New York, also a near four-year low.Later on London's InterContinental Exchange (ICE), Brent North Sea crude for delivery in January recovered to stand at...