There are three boxes: one contains apples, one contains oranges, and one contains both. The boxes are labeled incorrectly. If you can only open one box and take one fruit, which box should you open to correctly label all the boxes?
In a group of five friends: Alice, Bob, Charlie, David, and Eva, Alice is taller than Bob but shorter than Charlie. David is shorter than Eva but taller than Bob. Who is the tallest among them?