NYT: The Obama administration laid out four different plans Friday for improving the fuel efficiency of cars and light trucks for the model years 2017 through 2025 but did not choose among them. A bit like a tardy student, it promised a better effort by the end of November to determine what “levels of stringency” it would propose. The four “scenarios” were laid out in terms of percentage improvement per year, ranging from 3 percent, which works out to 47 miles per gallon by the 2025 model …