Argon is flowing between two chambers through a 10 m horizontal pipe of internal diameter 15 mm. Absolute pressures in each chamber are measured to be 250 kPa and 103 kPa, respectively. The flow is isothermal at 50C, the gas behaves ideally, the atomic weight of argon is 40 g/mol, and the friction factor () is 0.001. A. Determine the mass flow rate of gas and the gas velocities at the entrance and exit of the pipe. B. If the pressure in the downstream chamber is reduced while the upstream pressure is fixed, what is the maximum gas velocity achievable, and where in the pipe will it occur? 80 C. Show that when this maximum velocity is reached, the upstream and downstream pressures are related by the following expression. (14 marks) L P D P -In (32 marks) P P -1 (8 marks) D. Describe what happens when the pressure in the downstream chamber is reduced below the value applicable under the conditions in part (c). (6 marks)