A、About every four minutes. B、About every five minutes, C、About every six minutes. D、About every seven minutes. CHow often do th

M: Excuse me, I’d like to go to the Post Office, but I don’t know how to use this ticket machine.
W: Well, just press this button. It is 2 dollars.
M: Thanks.
W: The train is coming soon. Please wait a moment,
M: All right. How often do the trains come at this time of the day?
W: Usually it comes about every six minutes.
M: OK, and where should I get off?
W: Just get off at the Post Office Station. That’s five stops from here.
M: I’ve got it. Thanks for your help.
W: You are welcome.