New York (CNN Business) Robinhood received a startling 3:30 am call from its clearinghouse during last week’s Reddit-inspired market chaos asking for the free-trading app to put up a staggering $3 billion, co-CEO Vlad Tenev said Monday. “This was obviously nerve-wracking,” Tenev told Tesla (TSLA) boss Elon Musk during an interview on the platform Clubhouse. […]