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 think we should accept his plan .
Person2:I'm afraid I can't agree with you .
Person1: Why ?
Person2:Simply because it's not practical at all .

Answer: formal

Question: Person1: What's taking you so long ?
Person2:Don't worry . I'm almost finished .
Person1: I need you to hurry up .
Person2:All right . I'm finished .
Person1: I think there's more you need to do .
Person2:What do you mean by that ?
Person1: My hair looks awful .
Person2:What don't you like about it ?
Person1: I just don't like my hair .
Person2:I'm sorry that you don't like it .
Person1: I won't be paying you for this .
Person2:I'm sure we can work something out .

Answer: informal

Question: Person1: It's the 17th week now , isn't it ?
Person2:Yes , it is .
Person1: Oh , the final exam is coming soon . I feel a little bit nervous .
Person2:Take it easy . There is still one more week left before the exam begins . Have you prepared for it well ?
Person1: No , I haven't began my preparations .
Person2:Then shall we make preparations together ?
Person1: Great . You can help me a lot with English .
Person2:All right . But I am very poor at math . Would you like to help me with my math ?
Person1: No problem .

Answer:
informal