Tropic film holds on to top spot :

Action spoof Tropic Thunder has held off competition from a number of new films to stay top of the North American box office for a second weekend.
The comedy, starring Ben Stiller, tells the story of a group of actors who end up fighting in a real war. It took $16.1m (£8.7m) in its second weekend.
It beat campus comedy The House Bunny which opened with $15.1m (£8.2m).
Futuristic adventure movie Death Race, starring British actor Jason Statham, opened in third with $12.3m (£6.7m).
The film, about a brutal car race of the future, is a remake of 1975 film Death Race 2000.