《死亡船：迷雾中的绝望与救赎》频率分布直方图平均数怎么算

　　Survivors of a tragic shipping collision are rescued by a mysterious black ship which appears out of the fog. Little do they realise that the ship is actually a Nazi torture ship which has sailed the seas for years, luring unsuspecting sailors aboard and killing them off one by one. 　　91 　　Those who survive the ghost ship are better off dead!