A、20% of the full price. B、80% of the full price. C、Half of the full price. D、Full price. B

M:Hi, I come to pick up my laundry. I brought it here a week ago.
W:Wait for a moment, sir. OK, here you are. We’ve ironed them for you already. Please check and see if there is any damage. M:I’m afraid that a button is missing.
W:I’m terribly sorry. You know we are so busy today and we forget to sew the button back on. Please wait a moment. It will be ready soon.
M:OK, please.
W:Would you like to have a look? Is it to your satisfaction?
M:Well, oh my God, there is another problem, I’m afraid. There is still a stain on the shirt.
W:It doesn’t seem like that. Sorry, sir. We’ve tried everything, but we’re not able to get it off the shirt.It was from the sugar I think.
M:It’s been several days now, I am not sure.
W:Yes, the sugar was burnt during the dry-cleaning process. And there you go.
M:Oh, that’s so bad. I know little about that. Is there a remedy for it?
W:I am awfully sorry. Please tell us about the stains before the dry-cleaning next time.
M:OK, I will.
W:This is a membership card. You can get a 20 percent discount next time.
M:Thanks a lot.
W:Hope to see you again. We will provide the best service.
9.What does the woman say about the missing button?
10.What do we know about the stain from the conversation?
11.How much will the man pay for the dry-cleaning next time?