When constructing the perpendicular bisector of line segment PQ , what would be the correct first step?

Question

I was asked about this during class I didn't grasp the concept too well and I have a test monday where this question will be asked as well so I would really appreciate it if someone could help me out and answer my question. 

 

A) Put the compass point on point P and draw a long arc. Be sure the opening is greater than 1/2 PQ 

 

B) Put the compass point on point P and draw a small arc. Be sure the opening is greater than 1/2 PQ 

Answer 1

The correct answer is A; the big arc must be drawn partly above segment PQ and partly below it.

subsequently, the SAME big arc (i.e same radius) will be drawn with compass centered at Q.

Two points of intersection of these arcs are then joined by a new line segment, which will be the perpendicular bisector of segment PQ.