Reuters: Automaker fleets would have to achieve substantially higher fuel efficiency — 47 to 62 miles per gallon — by 2025 under a preliminary plan to further slash U.S. gasoline use released by the Obama administration Friday. Gasoline/electric vehicles and electric cars would be crucial to meeting the higher-range targets, according to the analysis crafted by federal environmental and transportation regulators. “We must, and we will, keep the momentum going to make sure that all …