The desperate search for Nancy Guthrie, the mother of NBC’s “TODAY” show co-anchor Savannah Guthrie, is ongoing, with mounting questions about what happened to her and concerns for her physical health. Nancy Guthrie, 84, was reported missing on Sunday from her home in the Catalina Foothills, an unincorporated community north of Tucson, Arizona. Authorities have described the case as a possible kidnapping or abduction, and there have been reports of ransom notes. Here’s what we know: Guthrie was