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: I really dislike reading academic books .
Person2:That may be so , but reading them is an important way to expand your knowledge .

Answer: informal

Question: Person1: Hey , Zina . You're here early today .
Person2:Yeah , I'm going to be making phone calls all day . What a blast .
Person1: I just wanted to say thanks for putting us on the map so fast . I appreciate it .
Person2:Save it , Vince . After I put my first million in the bank , I'll say you're welcome .
Person1: Fair enough.Keep up the good work .

Answer: informal

Question: Person1: Is this the foreign exchange department ?
Person2:Yes , can I help you ?
Person1: I need some US Dollars .
Person2:What kind of currency have you got ?
Person1: RIB . By the way , what is the exchange rate today ?
Person2:One US Dollars in cash is equivalent t0 7.9 Yuan .
Person1: And I want to change 4000 Yuan .
Person2:Minus the fee . Here are your dollars . Please sign here .
Person1: OK , thank you .

Answer:
formal