Detailed Instructions: 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.
Q: customer: Hi. 
 agent: Hello. How can I support you today? 
 customer: I am Christine Jones. Could you please help me to book an economy class ticket within the fare limit 5000 to Atlanta? 
 agent: Sure, I am glad to help you. May I know your airport codes? 
 customer: My airport codes are from CA-OAK to GA-ATL. 
 agent: Can you please forward your journey dates? 
 customer: I will depart on 12/20 and my return date would be on 12/22. 
 __ 
 customer: Sure. 
 agent: Thanks for your time, we found a connecting flight 1000 in AA airline with fare 100 in economy class. Shall I proceed with booking? 
 customer: Yes, you can proceed with the booking. 
 agent: Your flight ticket has been reserved. 
 customer: Thank you for your kind service in booking. 
 agent: Thank you for reaching us.
A:

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
agent: Please hold on.