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'.

Person1: Are these your text books ? Biochemistry , General Ecology , Botany , Cell Genetics , Molecular Genetics ...
Person2:Yes . I gotta review all of them for the final exam . It is just around the corner .
Person1: Oh , right ! Do you have many exams at the end of each semester ?
Person2:That depends . Some semesters have many , some don't . And some courses don't have exams but only ask for papers . That's easy .
Person1: And when do you prepare for your final exam ?
Person2:Honestly speaking , most students prepare it one month before the exam .
Person1: Really ? You only review your lessons in one month ? Does it work ?
Person2:Of course , it's useful . And it's very crucial to have the copies of teacher's notes , because most questions in the exam are based on them .
Person1: Wow , and all the key points are included in them ? You're so smart !
Person2:But the exam is not as simple as you may imagine . We have to stay up late .
Person1: Do you have the classrooms open for the whole night ?
Person2:Yes , some people even pack up his bed quilt and sleep there . That's a little bit crazy .
informal