BROADCAST FINALS ABC:  SHARK TANK fell 0.15 to 0.60, and 20/20 was down 0.16 to 0.54. CBS:  UNDERCOVER BOSS gained 0.05 to 0.54, MAGNUM PI edged up 0.02 to 0.50, and BLUE BLOODS was up 0.03 to 0.48. NBC:  THE WALL was...