Highest change of the temperature put the two trends lines that show the maximum change in the temperature.  From the lowest ratio of the stoichiometric one line is drawn, along with the other line is drawn from three points where the ratio of the stoichiometric is highest

References of Chemical Reaction Engineering

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TURANYI, T., & et al. (2012). Determination of rate parameters based on both direct and indirect measurements. International Journal of Chemical Kinetics, 44(5), 284–302.