Problem #4 The 72 teaching faculty of Khoury College are all represented in a social network graph. A person is a vertex in this graph. An edge between two vertices indicates that they are friends and hang out outside of work. Let's assume that friendship goes in both directions; if Laney is friends with Keith, then Keith is friends with Laney. It is not possible for someone to be their own friend. It is possible for someone to have no friends :( Make a strong, clear argument that at least two faculty members are guaranteed to have the same number of friends.

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