Geometry
posted by John .
7 points are placed in a regular hexagon with side length 20. Let m denote the distance between the two closest points. What is the maximum possible value of m?

Do not post any more questions until you've shown some evidence that you've tried to solve these problems yourself.
These multiple posts indicate that you just want someone to give you answers. Jiskha tutors do not do that. 
It is 20.
Asits maximum value of m is wanted. So it is 20 as the lenght of side is 20. So, the maximum value is 20.