Definition: 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'.
Input:  Person1:       Excuse me , could you tell me where you have got that music book ?  
 Person2:Certainly . Let me see . Oh , it's on that self .  
 Person1:        It's too high . I can't reach it . Could you help me ?  
 Person2:Of course . Here you are .  
 Person1:        Thank you very much . 

informal