Given the task definition and input, reply with output. 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: I'm exhausted . My new exercise class is so hard ,
Person2:I think it is easy . I could work in your class with no problem .
Person1: You thing so ?
Person2:Oh , without a doubt . When is the next class ?
Person1: Tomorrow morning . Try it .
Person2:No problem .
Person1: Are you going to this class this morning ?
Person2:Of course , easy . No sweat .
Person1: You're no able to move after this class .
Person2:Are you kidding me ? It's going to be up a piece of cake .
Person1: You want to bet ?
Person2:Yeah , what't the bet ?
Person1: I bet I can go one hour in your class this morning and not feel a thing .
informal