Corn is an excellent energy feed, and is ideal for finishing feeder pigs because it is high in digestible carbohydrates, low in fiber, and is very tasty feed for pigs to pigs! But corn alone will not keep pigs growing and healthy. Corn must be supplemented with Pig(s) food(s) vitamins to keep pigs healthy.
Pi is the ratio of a circle's circumference to it's diameter. The resulting number is the reason there cannot be a perfect circle. It's value is approximately 3.142 which, rounded up to the nearest whole number, would be four. It would not be three, as that would be rounding down.
Succinctly, pi--which is written as the Greek letter for p, or --is the ratio of the circumference of any circle to the diameter of that circle. Regardless of the circle's size, this ratio will always equal pi. In decimal form, the value of pi is approximately 3.14. But pi is an irrational number, meaning that its decimal form neither ends (like 1/4 = 0.25) nor becomes repetitive (like 1/6 = 0.166666...). (To only 18 decimal places, pi is 3.141592653589793238.) Hence, it is useful to have shorthand for this ratio of circumference to diameter.