The Rock County Medical Examiner’s Office has released the name of a 17-year-old Beloit boy who died in a single-vehicle traffic crash this week.  The victim is identified as Silas H. Wam.  According to the initial news release, the Rock County Sheriff’s Office responded to the crash on State Highway 213 between South Kettle and South Smythe School Roads just before 12:30 p.m. Wednesday.  Investigators determined the teen was headed north on 213 when his vehicle drifted to the east shoulder, left the road, went down a ravine, and came back up hill, hitting a tree and power pole.  Authorities report Wam was wearing a seatbelt.  Preliminary autopsy results show he died from injuries he suffered in the crash.