TAIPEI, Taiwan - A U.S. company that specializes in underwater work arrived in Taiwan on Friday, joining the search for clues about why a China Airlines jet plunged into the Taiwan Strait last month, killing all 225 on board, an investigator said Friday. Since the crash three weeks ago, the Taiwanese have been unable to recover the plane's "black boxes," or voice and flight data recorders. Strong tides and low visibility have hindered the search. "Visibility has been so poor that divers can't even see their feet," chief investigator Kay Yong said. The U.S. company that joined the search, Global...