The large tank contains air at an absolute pressure of $600 \mathrm{kPa}$ and temperature of $70^{\circ} \mathrm{C}$. The nozzle has a throat diameter of $20 \mathrm{~mm}$ and an exit diameter of $50 \mathrm{~mm}$. Determine the absolute pressure within the connected pipe, and the corresponding mass flow through the pipe, when the nozzle chokes and maintains isentropic supersonic flow within the divergent portion of the nozzle.