{TAIL ~ An amount} of {HEAD ~ exhaust} coming out of each opening 48 may be the same or may be different 
{ TAIL ~ An amount } of { HEAD ~ exhaust } coming out of each opening 48 may be the same or may be different
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH