This is the phew calculation.

For r=1, s=1.4142, when you've defined that the right length of the r=1's circumference equals 0.7071 or 70.71 % of the cone's total circumference. C= 0.7071 × 6.34314 × 1.41421 = 6.34314, you'll substract the circle area by 105.44°.

Then you've got a cone with h=1.

Now go to cylinder. How to define the cylinder's circumference?

2 pi.r?

Nope.

It's 2 PHEW.r

So why going far by calculating the earth's circumference, or distances, or area bla bla bla IF your pi is wrong.