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 am really interested in buying this television .  
 Person2:That's great !  
 Person1:        How much are you selling it for ?  
 Person2:This TV is $ 2500 .  
 Person1:        You can't be serious .  
 Person2:That's how much this t . v costs .  
 Person1:        That's too expensive for me .  
 Person2:This television is of very high quality .  
 Person1:        You can't go down on the price ?  
 Person2:By how much ?  
 Person1:        I'll buy it for $ 2000 .  
 Person2:I'm sorry , but the price is final . 

informal