Next, we need to approximate the total number of potential secondary (non-operator, non-Op) binding sites for the lac. To do this, we need to appreciate that there are 5 million base pairs in the bacterial genome, and we make the assumption that all possible secondary binding sites are equivalent in terms of binding affinity - thus, we can make the simplifying assumption that there are a total of ~5 million secondary binding sites. Using this information, calculate the concentration of secondary binding sites in one cell. (see eq. 13.19)