How much should the woman pay for the ticket?

M: The single fare is $832 first class and $516 second class. And the return fare is the same price.
W: Second class, with a return ticket, please.
Q: How much should the woman pay for the ticket?

M: Can you tell me when I can catch the next bus to the Medical School? It seems like I’m going to be late for my class this morning. It’s already 7:38.
W: Well, you just missed a bus by 4 minutes. Then you’ll have to wait another 15 minutes for the next one.
Q: When did the bus leave according to the conversation?