Melancholia - 1x01 - 1화- Followmy.tv

At Asung High, Yoon-soo’s new workplace, she gives a tricky question for students who want to join the math club. While no one in the class got the question right, a correct answer sheet is posted on the board outside the classroom. To find out who did it, Yoon-soo provokes them and manages to find who it is.