Q: 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: What's this city famous for ?
Person2:Tea and silk .
Person1: Where can we have the famous tea ?
Person2:Preferably at the big department stores .
Person1: Thank you .
A:
formal