A snowmobile has a front suspension and ski assembly having a right side and a left side. A finite set of a finite number of Gish distance values is descriptive for the relation of the unclassified piece of music to be classified with respect to a discrete and finite set of a finite number of music classes. Respective one of the metal layers has, on the surface of a sheet-like first metal, a second metal more susceptible to oxidation than the first metal. The perceptual model uses a dual-stage motion-based image difficulty measuring scheme to equalize contributions from the three image components in a manner that video artifacts in the output signal are least perceptive. Use of glucosamine salts can, therefore, provide neutrophil function inhibitors, preventives andor remedies for diseases caused as a result of an excessive extracellular release of active oxygen and antibiotic proteins by neutrophils, and also methods for the prevention andor treatment of such diseases.