As we said in the previous question, the Weber–Fechner law applies to all our senses, including smell. An example of this is shown in Fig. 4.12, which is reproduced from Fig. 2 of Wu et al (2016). For a number of odorous compounds they plotted the odour intensity as a function of odour concentration; the results for benzene are shown in the figure.

Show that k ≈ 2.6 in the Weber–Fechner law when applied to these data.