omar villafranca, cbs news, chattanooga, tennessee. >> o'donnell: can't get better unless you revisit the mistakes of the past. we'll be right back. wear this d. it continuously sends my glucose numbers to my phone, and this arrow shows me where i'm headed and how fast. check out dexcom.com/inrange. it's time for electric... to turn into lightning. ♪ an electric truck that can haul... ...on both ends. that can help build your house. and if need be, power that house. that feels like a bullet train. and works like a freight train. the fully electric f-150 lightning. age-related macular degeneration may lead to severe vision loss, so the national eye institute did 20 years of clinical studies