Dow closed up 42.84 points on news of falling oil prices to end the week at 12,004.36, while housing stocks closed mixed.  The Manufactured Housing Composite lost 1.87 percent to close at 926.90.  ELS gained 2.67 percent, Nobility Homes was up 1.67 percent and Sun Communities gained 1.09 percent.  Skyline Corporation dropped 3.95 percent, Palm Harbor Homes lost 2.44 percent, MSCI fell 1.64 percent and Cavco lost 1.31 percent.  Deer Valley was flat.