The United States set a world record of seven minutes, 50.09 seconds to win the women's 800-meter freestyle relay final at the world championships on Thursday. The American combination of Natalie Coughlin, Dana Vollmer, Lacey Nymeyer and Katie Hoff wiped 0.73 off the previous record of 7:50.82 set by Germany at last year's European championships in Budapest. (WCSN, WCSN.com)