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:       May I help you ?  
 Person2:I need to copy some pages in my book .  
 Person1:        The copier is right over there , in the corner .  
 Person2:Do I need to pay to use it ?  
 Person1:        You have to pay to use the copier .  
 Person2:How much do you charge ?  
 Person1:        You need to pay ten cents for every copy .  
 Person2:Is there a maximum number of copies I can make ?  
 Person1:        You can make as many copies as you want .  
 Person2:I ’ m going to need you to show me how to use the machine .  
 Person1:        There are instructions posted on the copier .  
 Person2:Thank you for your help . 

formal