AB is a line segment which is 8 cm long. CD and EF are parallel to AB, at a distance of 4 cm from it. GH is a line segment parallel to AB, at a distance of 2 cm from it. PQ is the perpendicular bisector of AB which intersects CD, GH, AB and EF at M, N, O and P respectively.
The point/s which is/are always at a distance of 4 cm from the line AB and equidistant from A and B is/are