Emergency responders in Milwaukee say they aren’t surprised.  Statistics show only one-in-five people will try to help someone in cardiac arrest.  When a violent crash happened Tuesday, surveillance video showed people walking, driving or riding a bicycle right by the scene without trying to help.  North Shore Fire Rescue says you don’t have to climb into the window of the car and pull people out — or, even administer first aid — but it would be a good first step to ask the people involved if they are okay.  Victims of Tuesday’s crash survived and didn’t require hospitalization.