“The Help” continues to clean up at the box office, taking over the No. 1 spot with $20.5 million in its second weekend. The drama about Southern black maids had debuted in second-place a week earlier. “The Help” raised its domestic total to $71.8 million and bumped “Rise of the Planet of the Apes,” which slipped to No. 2 with $16.3 million after two weekends at the top.