Additional steps are having {HEAD ~ a central computer} monitor inventory levels, track {TAIL ~ part request}, and order replacement parts when inventory levels fall below a preset level 
track
Additional steps are having { HEAD ~ a central computer } monitor inventory levels , track { TAIL ~ part request } , and order replacement parts when inventory levels fall below a preset level
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH