On March 14 (3/14) we celebrate Pi! When you multiply the width of a circle by pi (3.14159265...), you get the distance around the edge. So we're celebrating some of our favorite circle-shaped foods, like oranges, lemons and limes. If you slice across any citrus fruit, you'll see a circle divided into little pie sections called "liths." The number can differ, but photos show that most lemons have 8 or 9 liths; oranges and limes have 10 to 12; and grapefruit can have 14 or more. And you can figure out the number before cutting the fruit -- read on to learn the secret!