How many millimeters are in 2 and 1/2 inches
25.4 x 2.5 = 63.5 millimeters.One inch is equal to 25.4 mm and 2.5 represents 1/2.
That one i dont know but wait ill get back to you on that
25? Arent there 10mm per inch? So it would be 10x2=20mm + half of an inch(5mm) so 25. Hope this helped but i could be wrong :)