Solution: The title refers to the fact that each item in this puzzle has been flipped backwards and had the bottom half cut off. Each column is made up of five such altered pieces stacked atop one another. The third column is the five vowels (AEIOU). The first column is made up of numbers (83?02). These five numbers contain the five hard vowel sounds in order (ex. "8" is pronounced with a hard "A", "3" with a hard "E"). The missing number would have to contain a hard "I" sound. One of the parts of the middle column is the top half of a backwards number "5", so that part (the second from the top) is the solution.