Teacher:In this task, you are given a conversation between a flight agent and the customer. You are given 4 options and you need to select the goal of the conversation. It is provided as part of customer's context, which has to be one of the following: `book`: Make a new reservation, `cancel`: Cancel an existing reservation, `no_flight`: No flight found for the customer's preference, `no_reservation`: No reservation / No change / No cancellation was made in the conversation, mostly enquiring details
Teacher: Now, understand the problem? Solve this instance: customer: Hello, I am Cynthia Miller. 
 agent: Hello, how can I assist you? 
 customer: Could you please help me in booking my flight ticket from DCA to OAK? 
 agent: Sure, let me know your travelling dates? 
 customer: My planned trip dates are 03/21 and 03/23. 
 agent: Please provide your specifications. 
 customer: My price limit is 1000. 
 agent: UA airlines with single connection and price is 200 of 1000 flight. 
 customer: Ok, please proceed. 
 agent: Your ticket has been confirmed. 
 customer: Thank you for your service. 
 agent: Thank you.
Student:
book