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:       How may I help you ?  
 Person2:There ’ s a problem with my check .  
 Person1:        What problem ?  
 Person2:My check for $ 100 bounced .  
 Person1:        Are you sure you have $ 100 in your checking account ?  
 Person2:I thought I did .  
 Person1:        I ’ ll check for you .  
 Person2:Thank you very much .  
 Person1:        It looks like you only have $ 57 left in your account .  
 Person2:That can ’ t be right !  
 Person1:        That ’ s what my computer is showing .  
 Person2:All right . Thank you very much . 

informal