Solve the following problems. Use all constants and properties in Perry's CHE Handbook. 6.2. Natural gas consisting essentially of methane is to be transported through a 20-in.-ID pipeline over flat terrain. Each pumping station increases the pressure to 100 lb,/in.? abs, and the pressure drops to 25 lbs/in.? abs at the inlet to the next pumping station 50 mi away. What is the gas flow rate in cubic feet per hour measured at 60F and 30 in. Hg pressure? 6.3. A divergent-convergent nozzle has the proportions shown in Table 6.1. Air (y = 1.40, M = 29.0) enters the nozzle from a reservoir in which the pressure is 20 atm abs and the temperature is 550 K. Plot the pressure, the temperature, and the Mach number vs. the length of the nozzle when (a) the flow rate is a maximum without shock and with subsonic discharge; (b) the flow is isentropic and the discharge is supersonic.