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:       Well , Mr . Brooks . I ’ m sorry , again , for the delay , but we should have everything completed by the time you get back .  
 Person2:I certainly hope so . Can we arrange to meet on the 27th ? That should give you enough time .  
 Person1:        Yes , sir . That ’ s more than enough time . I do appreciate your understanding . Why don ’ t we say 10:00 o ’ clock on the 27th ?  
 Person2:Fine , Mr . Tan . I ’ ll see you then . 

informal