听力原文：Jim: Helen, when is Tom's birthday? Is it this week? Helen: Yeah, it is this Friday, the twenty-eighth. Jim: I'd like to see him on his birthday. Are you two doing anything? Helen: Well, yes, we have tickets to a concert at Carnegie Hall. Jim: What time does it start? Helen: It starts at 8: 30. Jim: Hmmm... I'm afraid I can't make it by then. I have to work late on Friday. Hold on... I have an idea. What time does the concert end? Helen: Pretty late. Probably around half past ten. Jim: Well, how about going to the Caf6 Alfredo for some coffee and birthday cake after the concert? I'll meet you there. Helen: Well, what time does the caf6 close? Jim: It is open until at least 1:00. Come on, admit it... it's a fabulous idea. Helen: OK, OK, Jim. We'll see you then. What is the possible relationship between the two speakers?