What is being constructed based on the markings in the following diagram?

line ab with two points c and d on each side of the line; a circle is created with center c passing through point d, and the intersection of circle c with line ab creates points e and f such that point a is between points e and f and point f is between points a and b. point g is not located on line ab and is on the same side as point d. a circle is created with center f and a radius of fg, and another circle is created with the same radius from point e. points h and i are intersecting points of circles e and f, and a line is drawn through points h and i.

inscribed regular hexagon
inscribed equilateral triangle
perpendicular line through a point off a line
perpendicular line through a point on a line