You will be given a definition of a task first, then some input of the task.
In this task, you're given a dialogue between a customer and a flight booking agent with a gap in the conversation. Your job is to find the answer of the previous dialogue. Avoid using irrelevant extra information while creating the answer. The answer should be relevant to the question before the blank. If you fill the blank with a question, it should have an answer from the agent in the given dialogue. Fill the gap marked with underline.

customer: Hello. 
 agent: Hello. How can I assist you? 
 customer: I'm planning to visit Las Vegas, can you book a ticket from DEN to LAS? 
 agent: Ok, please can I know your name to proceed? 
 customer: Sure, my name is Ashley Johnson. 
 agent: Ok, please can I know your dates of journey? 
 customer: I would like to depart on 7th Oct and I want to return back by 9th Oct. 
 agent: Ok, please let me know your specifications. 
 customer: I'm looking for single connected flight. 
 agent: Is there any other requirements? 
 __ 
 agent: There is a flight ticket available at the location you need for the airfare 100 and the airlines is American Airlines. Can I book the flight 1000? 
 customer: That's fine, you can proceed for booking the ticket. 
 agent: Ok, the class is economy for which the ticket is confirmed. 
 customer: Thank you so much for your help. 
 agent: Thank you for choosing our agency.
Output:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
customer: No, I don't have any other specifications.