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'.

[EX Q]: Person1: Good afternoon , everyone . The experiment is to start at 3 . Have you gone through the instructions ?
Person2:Yes , sir .
Person1: Ok , now some points for attention . First of all , pay attention to safety ... Now , sign your names on the lab record , and after that you can start . If there is any question , just let me know .
Person2:Excuse me , sir . This air compressor doesn't work .
Person1: Have you turned it on ?
Person2:Yes , I have .
Person1: Ok , I will get you another one .
Person2:Thank you .
[EX A]: formal

[EX Q]: Person1: I'm tired .
Person2:Okay , let's call it a day .
[EX A]: informal

[EX Q]: Person1: Oh , Linda . You must be so excited about going to study in America .
Person2:Oh yes I am . I have always wanted to go to the States . I love meeting new people and making new friends .
Person1: Well , I am sure you will .
Person2:Well , there is one thing .
Person1: What is the matter ?
Person2:I am a little worried about my host family . You know , in the agreement , I have to do some cooking for them .
Person1: Yes ?
Person2:Well , I am just afraid they won't like my Chinese way of cooking .
Person1: Oh , listen , you'll soon learn , and I am sure they will explain to you how they like to get prepared .
Person2:Oh , let's hope so .
[EX A]:
formal