Answer:
I want to say 5 lines are parallel to line FM.
Explanation:
I can see that lines (or edges) AG, BH, CJ, DK, and EL are parallel to the edge FM. They don't intersect with each other and are all going straight up and down. A line (edge) that will never touch edge FM would be edge HJ. HJ is going straight left to right while FM is going straight up and down. These two edges are not parallel.