Answer: Refer to the picture I've attached.
Step-by-step explanation:
As far as I know a pyramid net has a square in the centre and 4 triangles, each joining an edge of the square.
Hope this makes sense and helps. :)
1 inch = 12 miles
so 6 1/2 inches (or 6.5 inches) = 6.5 * 12 = 78 miles <===