Consider the PCM Furnace module of Appendix E, which is used to preheat a high-molecular-weight hydro-carbon feed (C₁₆ – C₂₆) to a cracking unit at a petroleum refinery.

Do the following sequence of simulations:
(a) Change the Fuel Gas Purity from the initialized value of 1.0 to a new value of 0.95, and start the simulation. Generate plots for the Oxygen Exit Concentration and the Hydro carbon Outlet Temperature. Record the starting values and final (steady-state) values for these variables.
(b) Once the system has reached a new steady state (and you have collected the information requested in part (a)), increase the Hydrocarbon Flow Rate by 10% over the current value. Generate plots for the Oxygen Exit Concentration and the Hydrocarbon Outlet Temperature. Record the starting values and final (steady-state) values for these variables.
(c) Comment on the relative differences between these two input changes (strength of effect, timing of response).