Misc: What gas in the blood of divers can cause the bends?

Questions

Video Games: Tetris game where the object is to stack objects on people's heads.?

World History : What was the Japanese warrior class that rose to power in the 11th century ?

World History : Where did the Incas originate ?

World History : Which aviator made the first non-stop flight across the Atlantic ?

World History : Which event triggered the Great Depression ?