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:       What are you calling about today ?  
 Person2:I scheduled a delivery for tomorrow .  
 Person1:        Is there a problem ?  
 Person2:I would like to reschedule .  
 Person1:        That shouldn't be a problem .  
 Person2:Can I have it delivered the day after tomorrow ?  
 Person1:        So , you want it delivered the day after tomorrow ?  
 Person2:Yes , will that be possible ?  
 Person1:        What time would you like us to deliver it ?  
 Person2:Is 2:30 Okay ?  
 Person1:        Your delivery has been confirmed .  
 Person2:Thank you , and I'm sorry for the change of plans . 

informal