Three animals want to cross a lake in a boat. There's an ape that weighs 800 pounds, a bear that weighs 500 pounds, and a lion that weighs 300 pounds. Their boat can only hold 800 pounds. They can't swim across the lake, walk around it, or hang off the edge of the boat. How can they use the boat to get across the lake? Can you tell who is in the boat for each trip? (Hint: the animals make five crossings)