A liquid drain withdraws the liquid constituent from the vessel at {HEAD ~ a rate} determined by {TAIL ~ a level assembly} 
determined by
A liquid drain withdraws the liquid constituent from the vessel at { HEAD ~ a rate } determined by { TAIL ~ a level assembly }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL