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'd like to buy one of these refrigerators . Do I have to pay in cash ? 
 Person2:No , we have an easy-payment plan . One-third down , and the balance in six months . 
 Person1:        Fine . Will you work out the details , please ? 
 Person2:Certainly . Would you sit here please ? I'll call our credit manager . 
 Person1:        Thank you . 
 Person2:It's just a formality , but for hire purchase we usually require references . 
 Person1:        What kind of references do you need ? 
 Person2:Perhaps your employer could supply us with one . 
 Person1:        I'm sure he could , but I prefer not to bother him . Would my bank do ? 
 Person2:Certainly . A simple letter from your bank would be quite satisfactory . 

informal