Practically on a whim, Joan Kroc made the biggest public radio pledge in history: around $250 million dollars to NPR. She could afford it. Her husband was McDonald's corporation founder Ray Kroc, and Ray and Joan were worth billions. Ray's life was well-publicized, most recently in the Michael Keaton film The Founder. That film is based on a true story. A new book from journalist Lisa Napoli might serve as a companion piece to the film, because the book is a true story, a meticulously-researched