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:       Give me Scotch , please .  
 Person2:What brand ?  
 Person1:        Black Rose .  
 Person2:Soda or water ?  
 Person1:        Just plain water with plenty of ice rock .  
 Person2:All right . Please wait for a minute . 

formal