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'.
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Question: Person1: Amy , could you help me with this work ?
Person2:Sorry , I'm busy . Why don't you ask Alice ?
Person1: Okay .

Answer: informal

Question: Person1: Jane's mother always wants her to marry a big shot . J
Person2:That is just wishful thinking . The cost of higher education has increased in recent years , faster than the cost of living . So she wants Jane's brother to go on studying and earn his doctorate by means of it .
Person1: But it's unfair for Jane .

Answer: informal

Question: Person1: Mr . : Are you Mary Lin ?
Person2:Yes .
Person1: Mr . : I'm Mr . Rogers , your homeroom teacher .
Person2:Where should I sit ?
Person1: Mr . : Why don't you sit behind Brad ?
Person2:Who's Brad ?
Person1: Mr . : He's that guy in the blue shirt .
Person2:When does the first period begin , by the way ?
Person1: Mr . : As soon as the bell rings after the morning announcement .

Answer:
formal