Question

if i I wanted to be precise, how can I express the exact circumference for the circumference given the diameter

Answer 1

The formula for circumference is $\pi d$.

To express the circumference exactly, plug the diameter in for $d$ and put the $\pi$ symbol in front of it. Don't multiply. This expresses the exact circumference.

Say you have the diameter of 17.
You can express the circumference with 17$\pi$.