In certain aspects, the PVT properties 250, e.g. densities of gas, oil/condensate and water of the multiphase stream from the sampling operation 230 of the IWSS 200, measured at pressure and temperature kept close to those in the main-pipe, may be used to provide inputs to the ???Nuclear Inputs??? 277 required by the nuclear densitometer and venturi flow meter 279 and the subsequent ???Wet Gas Mod