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:       Hello , what can I do for you ? 
 Person2:Hello , I come to pay my water and electricity fees . 
 Person1:        Give me your water and electricity bills , please . 
 Person2:Here they are . 
 Person1:        You should pay 160 yuan for the electricity fee and 80 yuan for the water fee . 
 Person2:Do you mean that I should pay 240 yuan in total ? 
 Person1:        Yes . Will you pay by cash or credit card ? 
 Person2:Cash , please . Here is the money . 
 Person1:        I get 250 yuan from you , and this is the change , 10 yuan . 
 Person2:OK . Thank you . Bye-bye . 
 Person1:        Bye . 

informal