Warren Buffett is interviewed by CNBC's Becky Quick at a fundraising event to benefit The Gatehouse, a "supportive living community for women," in Grapevine, Texas. He says economic growth has slowed a bit. While he supports free trade, he thinks the U.S. has an obligation to take care of people who become "roadkill" as a result of economic forces beyond their control. He also speaks about Boeing's 737 Max jet problems, buying more Delta Air Line shares, and embattled Wells Fargo CEO Tim Sloan.