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:       Excuse me . Mr . Li . May I ask you some questions ? 
 Person2:Sure . Take a seat , please . What would you like to know ? 
 Person1:        Can you tell me how many credits would be enough for a Bachelor's degree ? 
 Person2:A Bachelor is awarded to a student who successfully completes over 120 units , including general and specific requirements , for his or her undergraduate major and elective courses . 
 Person1:        How long does it take to earn a Bachelor's degree ? 
 Person2:Normally it can be completed in four years . 

formal