This month, we have four related questions.

- Find a configuration of 7 points in the plane such that among any three of them at least one pair of points is one unit apart.
- Is it possible to find a configuration of 8 such points in the plane?
- What is the largest number of points in a planar configuration such that among any four of them at least one pair of points in one unit apart?
- What is the largest number of points in a configuration in three-dimensional space such that among any three of them at least one pair of points in one unit apart?

Source: Generalizations of a question from the USA Mathematical Talent
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