Union Pacific hopes the new application it filed Thursday will be enough to persuade regulators that its $85 billion acquisition of Norfolk Southern would be good for the country. The U.S. Surface Transportation Board rejected Union Pacific's initial application because regulators wanted more details about how the deal would affect the competitive balance between the five remaining major freight railroads and the impact on customers. Union Pacific CEO Jim Vena said the new application makes an even stronger case for the benefits of the merger that he believes would shave a day or two off the delivery time for many shipments because they would no longer have to be handed off between two railroads in the middle of the country. The Omaha , Nebraska-based railroad projects that the merger could lead to shifting 2.1 million truckloads off the highway onto trains.…