Geometry construction help: Kathy uses the following steps to construct a perpendicular line through a point C on a line segment:

Step 1: From point C, draw two arcs intersecting the line segment in points A and B.
Step 2: Using slightly more compass width, draw two arcs from point A, one above and the other below the line segment.
Step 3: Using the same width of the compass, draw two arcs from point B, above and below the line segment.
Step 4: Label the point of intersection of the arcs above the line segment as F and below the line as E.
Step 5: Using a compass, join E and F.

Question

Geometry construction help: Kathy uses the following steps to construct a perpendicular line through a point C on a line segment:

Step 1: From point C, draw two arcs intersecting the line segment in points A and B.
Step 2: Using slightly more compass width, draw two arcs from point A, one above and the other below the line segment.
Step 3: Using the same width of the compass, draw two arcs from point B, above and below the line segment.
Step 4: Label the point of intersection of the arcs above the line segment as F and below the line as E.
Step 5: Using a compass, join E and F.

anonymous · Answer

Part A: Which is the first incorrect step?
Part B: Using complete sentences, explain your answer for Part A.
Part C: Explain why a compass works for the construction done by Kathy.