c - Attendant: Can I help you?
h - Customer: Yes. Can I have a sandwich, please?
a - Attendant: That's £3.25, please.
f - Customer: Yes, please.
g - Customer: Here you are.
b - Attendant: Thank you. And here's your sandwich.
e - Customer: Thanks.
d - Attendant: Yes, OK. Would you like cheese in it?