A. we are all booked up for Flight 802 on that day.B. I'd like to make a reservation to Boston next week.C. what about the fare? Agent: Good morning. The United Airlines. What can I do for you?Caller: Yes,【D1】______Agent: When do you want to fly?Caller: Monday, September 12.Agent: We have Flight 802 on Monday. Just a moment please. Let me check whether there're seats available. I'm sorry【D2】______Caller: Then, any alternatives?Agent: The next available flight leaves at 9- 30 Tuesday morning September 13. Shall I book you a seat?Caller: Er...It is a direct flight, isn't it?Agent: Yes, it is. You want to go first class or coach?Caller: I prefer first class, 【D3】______Agent: One way is $ 176.Caller: OK. I will take the 9: 30 flight on Tuesday.Agent: A seat on Flight 807 to Boston 9' 30 Tuesday morning. Is it all right, sir?Caller: Certainly.