Who is the woman talking to?

W: Hi, I have some product samples I want to send overseas. Could you tell me which option has the least expensive rate?
M: Well,(56)overnight delivery shouldn’t take more than a day, but it is pretty expensive, regular mail takes five days to ten days. If you send it by ship, it’s cheaper but it takes about 20 days.
W: Well,(57)the samples have to arrive within three to five days.(58)Besides, they are fragile items that need to be handled with caution.
M:(57)If that’s the case, overnight delivery would be the best. Regular mail might deliver it in a week or so, but it could take a little longer. Overnight delivery is much safer than other options.