Power generator 26 and {HEAD ~ second power generator} 28 may provide {TAIL ~ equal power} or may provide different power amounts  
provide
Power generator 26 and { HEAD ~ second power generator } 28 may provide { TAIL ~ equal power } or may provide different power amounts
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH