Who is asking: Student
Level of the question: All
Question: A small business has 8 employees. Every day, the owner designates a team to do a certain task. The owner is careful never to designate a team that is a subset of a former team or a future team, because then some people might feel not really needed in some teams. Prove that even being so considerate, the owner can choose a different team on each of 70 consecutive days.