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:       I haven't got enough evidence for prosecuting him .  
 Person2:Why don't you find someone who is in the know .  
 Person1:        I'm just thinking about that , but the trouble is , I don't know who is well in the know .  
 Person2:Did you ask his former secretary , Lora ? She knows a lot about him .  
 Person1:        Thanks for reminding me . She's the right person to help me . 

informal