Mercury News: Next month California voters will have the opportunity to invest in a major piece of infrastructure that will shape California’s 21st century future – high-speed rail. The project would link San Diego, Los Angeles, San Francisco and Sacramento with 200-mph trains on a route running through the fast-growing Central Valley. Big dollars – $9.5 billion – are involved, a down payment on a total project cost approaching $40 billion (the balance of funding would come from federal and private …