{HEAD ~ The speed} of {TAIL ~ propagation} is predetermined by the inherent characteristics of the wave and the medium chosen 
{ HEAD ~ The speed } of { TAIL ~ propagation } is predetermined by the inherent characteristics of the wave and the medium chosen
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH