U.S. stocks fell sharply Friday, concluding a volatile week, as heightened speculative trading by retail investors continued to unnerve the market. The Dow Jones industrial average fell 620.74, or 2 percent, to 29,982.62. The broader S&P 500 fell 73.14, or 1.9 percent, to 3,714.24. The technology-heavy Nasdaq composite index fell 266.46, or 2 percent, to 13,070.69.
