Final answer:
The lunch-hour manager at Gavi's Fast Food Restaurant resolved a complaint about the payment line system by implementing floor markings, resulting in no further complaints, reduced stress for clerks, and efficient customer service.
Step-by-step explanation:
The customer complaint regarding the inefficiency of the payment line system at Gavi's Fast Food Restaurant was addressed by the lunch-hour manager, who was tasked with resolving customer complaints and improving service. To tackle this issue, the manager took customer feedback seriously and implemented a solution involving floor markings to guide customers to the correct lines for payment. This action led to a significant improvement, with no subsequent complaints about the line-up process, reduced stress for the customer service clerks, and a higher throughput of customers served efficiently.