Any True Christian knows that Pi=3 for this is proven to us in scripture.
And he made a moulten Sea, ten cubites from the one brim to the other: it was round all about, & his height was five cubits: and a line of thirtie cubites did compasse it round about. (Kings 7:23)
However, experiments are fun. And this is one you can show to anyone and do on your own easily! Here we go. Find a circle, this can be online or printed. We know that Pi is defined as the ratio of circumference over diameter. So, measure the diameter. Next, measure the circumference. THAT'S RIGHT! IT'S IMPOSSIBLE! Because your tool of measurement will intersect at one point, there is no way for us to measure the length of the circumference. And we cannot unravel it, only God can! And God says that the ratio of circumference over diameter (or Pi) is exactly 3. So there you go, try this for yourself!