Top EPA officials are downplaying the effect of low gasoline prices on the administration's flagship greenhouse gas (GHG) and fuel economy program for vehicles, saying a few months of low prices will not force the agency to ease the light-duty rules as many top auto industry executives are seeking ahead of the program's upcoming mid-term review. But the agency officials say they plan to continue to monitor whether fuel prices are effecting industry's compliance with the current mandates for model...