{HEAD ~ the pressure determination system} is operable to determine the pressure values by determining a first pressure value and a second pressure value of the fluid at {TAIL ~ a first time} and a second time, respectively, during the oscillation of the pressure, and 
{ HEAD ~ the pressure determination system } is operable to determine the pressure values by determining a first pressure value and a second pressure value of the fluid at { TAIL ~ a first time } and a second time , respectively , during the oscillation of the pressure , and
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH