Convert from button measure to parasang

Unit Definition (button measure)
The button measure is a unit of distance equal to 1/40 inch (0.635 millimeter), used to measure the thickness of buttons.

Unit Definition (parasang)
The parasang (Persian - farsang) is an ancient Persian unit of itinerant distance corresponding to approximately 3.5 miles (5.6 kilometers)., or the distance that can be traversed on foot in an hour.