Amid the hunt for "Today" cohost Savannah Guthrie's mom Nancy Guthrie, TMZ and an Arizona CBS News affiliate report receiving demands for millions in Bitcoin for her release. TMZ said its note demanded millions of Bitcoin cryptocurrency and provided a specific Bitcoin address. The outlet reported that it has verified the validity of the address. While investigators continue to evaluate the validity of the notes, some Americans may wonder if the Bitcoin address would be enough to find the culprit or at least narrow the search for the kidnapper. It's not that simple. Here’s what to know about Bitcoin (full story)