Geometry, the mathematics is of course a very exact science and you need to have the analytical part of the mind that all this pulling. No, write in the comments to this video that... you have a sexual appliance as much as 26 centimeters, then you need an ordinary ruler, IQ doesnt really need one, it is clear that you are confusing millimeters and centimeters and a priori stupid. We have a similar situation with a guy before which the question arose to teach geometry, or to fuck soft and flabby women. The choice is obvious.