A $4.7 billion plan to build high-speed rail lines and expand bus service in the Denver area would add about 6,200 jobs a year and give a lift to the local economy, a new study showed. Over a 12-year development period for the project, known as FasTracks, about 2,400 construction jobs would be created annually, and 3,800 positions would be added indirectly, according to a report requested by the Metro Denver Economic Development Corp. As construction companies spend money on everything from concrete to computers, even more jobs would arise, creating an economic ripple that could inject $2.9 billion in...