Answer:
a. identical, b. clients or customers
Explanation:
It is a known fact that in almost every business environment there are competitors.
The principle holds that firms competitors make themselves identical by clustering in one physical location eg a market.
To appeal to the maximum number of clients, it was observed that consumers often prefer the nearest of two options when making purchases. Meaning the maximum concentration of clients would usually be where clusters of identical firms are located, because the clients fill they have more options available since the firms are not distant apart.
