You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. You are required to assign a label 'formal' if there is an absence of emotion and a presence of questions anywhere within the conversation. If such pattern is not found assign the label 'informal'.
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Question: Person1: Excuse me , I bought this sweater yesterday . But when I got home and tried it on , I found it ' s too small .
Person2:Do you have the receipt with you ?
Person1: Yes , here you are .
Person2:Thank you . Do you want your money back ?
Person1: No , can I exchange it for a bigger one ?
Person2:I am afraid this is the biggest size we have .
Person1: Oh , that's too bad .
Person2:Maybe you would like to try this one with the willow pattern . The price is the same and it's bigger .

Answer: formal

Question: Person1: Why do you want to be a teacher ?
Person2:It's a job I've been dreaming of since I was very little . I firmly believe that teaching is one of the most honorable jobs in the world .
Person1: In what department do you wish to work if we hire you ?
Person2:I want to work in the English Department , as I am an English major .

Answer: formal

Question: Person1: Hello , Sir . What can we do for you today ?
Person2:Hello . I've been asked to come and see about something called L / C ? What is it exactly ?
Person1: L / C stands for ' letter of credit ' . This is necessary for trade between two countries . A Letter of Credit is quite literally that a letter addressed by the buyer's bank to the seller's bank stating that they could vouch for their good customer , the buyer , and that they would pay the seller in case of the buyer's default . Nowadays , it's sometimes used for domestic trade too .
Person2:So the other party could be across the world or just on the other side of the street !

Answer:
formal