Such signals may thus demonstrate {TAIL ~ a relationship} between the pressure signal 302 and the density signal 304, as those signals change over {HEAD ~ time} 
Such signals may thus demonstrate { TAIL ~ a relationship } between the pressure signal 302 and the density signal 304 , as those signals change over { HEAD ~ time }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD