U.S. stocks rose strongly Thursday, the Dow Jones industrial average rose 332.26, or 1.1 percent, to 31,055.86. The broader Standard & Poor's 500 index rose 41.57, or 1.1 percent, to 3,871.74. The technology-heavy Nasdaq composite index rose 167.20, or 1.2 percent, to 13,777.74.