Masks are no longer mandated on public transportation, after a federal judge in Florida ruled that the CDC had overstepped its authority when it issued a mask mandate for planes, trains, and buses. Sara Nelson, international president of the Association of Flight Attendants, discusses whether customers and employees will continue to use masks to protect fellow travelers. Plus, as Elon Musk explores options to finance his bid to buy Twitter, biographer and Tulane professor Walter Isaacson shares insight on Musk’s goals and motivations from extended conversations with Elon Musk himself.  In this episode:Walter Isaacson, @WalterIsaacsonSara Nelson, @FlyingWithSaraAndrew Ross Sorkin, @andrewrsorkinJoe Kernen, @JoeSquawkCameron Costa, @CameronCostaNY