Final answer:
If a vehicle shows up to the service center fifteen minutes before open, the appropriate action would be to let the vehicle in and begin servicing it.
Step-by-step explanation:
If a vehicle shows up to the service center fifteen minutes before open, the appropriate action would be to let the vehicle in and begin servicing it. The service center should not turn away customers who arrive early, as it is their responsibility to provide service during their stated hours of operation. By promptly attending to the vehicle and providing the necessary service, the service center can demonstrate good customer service and ensure customer satisfaction.