With the average price of gasoline in the United States above $4.50 a gallon — about a 40 percent rise since the Iran war began in late February — Americans have been climbing into their cars less often, and stepping onto trains and buses instead. It’s been declared the largest oil supply disruption in history, with U.S. drivers paying $45 billion more for gasoline and diesel compared to last year. Some 44 percent of U.S. adults say they’ve cut back on driving because of high gas prices, according to a survey in late April from ABC News, The Washington Post, and Ipsos. Cities across the country have seen rising numbers of people riding public transit , from Cincinnati to Los Angeles . Sales of used electric vehicles and hybrid cars have grown substantially over the past couple of months. People are replacing car trips with bikes and scooters ; railroads like Amtrak have reported more riders than usual .…