Let F be a family of hexagons H satisfying the following properties:
i) H has parallel opposite sides.
ii) Any 3 vertices of H can be covered with a strip of width 1.
Determine the least ℓ∈R such that every hexagon belonging to F can be covered with a strip of width ℓ.
Note: A strip is the area bounded by two parallel lines separated by a distance ℓ. The lines belong to the strip, too. geometrytrigonometryrhombuscombinatorics unsolvedcombinatorics