Pepper stand at Central Market in Houston, Texas, with Scoville scale. Unlike methods based on high-performance liquid chromatography, the Scoville scale is a subjective measurement dependent on the capsaicin sensitivity of testers and so is not a precise or accurate method to measure capsaicinoid concentration.
By definition, pi is the ratio of the circumference of a circle to its diameter. Pi is always the same number, no matter which circle you use to compute it. Unlike some responses on this forum, PI does not equal 22/7 there is a slight difference.
Pi is a number that is approximately equal to 3.14. It is the number you get if you divide the circumference of any circle by its diameter. It's the same for all circles. You can approximate pi for yourself by taking some circular things like the tops of jars and CD's and frisbees and measuring their diameter and their circumference.