A large reservoir at 20oC and 800 kPa is used to fill a small insulated tank through a converging-diverging nozzle with 1-cm2 throat area and 1.66-cm2 exit area. The small tank has a volume of 0.9 m3 and is initially at 20oC and 100 kPa. Estimate the elapsed time when (a) shock waves begin to appear inside the nozzle and (b) the mass flow begins to drop below its maximum value.