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 in the world is that smell ?  
 Person2:The aroma of roasting coffee beans .  
 Person1:        Smells like you're baking something . What are those ?  
 Person2:Green beans . They pop and turn brown when you roast them .  
 Person1:        Cool ! But isn't that a hot air popcorn popper ?  
 Person2:This machine roasts the beans just right . If you roast them too long , or the temperature is too hot ...  
 Person1:        The beans will burn . I know . I've tasted burnt coffee before ... yuck ! 

informal