Answer:
Alpha
Beta
Delta
Epsilon
Zeta
Explanation:
The customers list should be updated and sorted periodically to identify regular customers and those customers with big orders. There are many customers in the list and the list is not sorted according to alphabetical order. Those customers which account for more than or at least 5% of total trade are Alpha, Beta, Delta, Epsilon and Zeta. These are place first in list among other customers.