A) construct a triangle ABC with AB=2cm, BC=6cm and CA=6cm. b) Construct inside triangle ABC the locus which are equidistant from AB and BC call this set R. c) construct inside triangle ABC the which are equidistant from B and C. Call this set S.

Draw a line segment AB of length 2 cm.

With A as the center, open your compass to 6 cm and draw an arc.

With B as the center, open your compass to 6 cm and draw another arc. This arc should intersect the first arc.

Label the intersection point of the two arcs as C. Draw line segments AC and BC to complete $\triangle ABC$.

The locus of points equidistant from two intersecting lines (AB and BC) is the angle bisector of the angle formed by these lines, which is $\angle ABC$.

Place the compass at point B and draw an arc that intersects both line segment AB and line segment BC. From each of these intersection points, draw another arc such that they intersect inside $\angle ABC$.

Draw a straight line from point B through the intersection point of the two arcs you just drew. This line is the angle bisector of $\angle ABC$, and it represents set R.
The locus is the angle bisector of $\angle ABC$.

The locus of points equidistant from two fixed points (B and C) is the perpendicular bisector of the line segment connecting those two points, which is BC.

Place the compass at point B and open it to more than half the length of BC. Draw an arc above and an arc below line segment BC. With the same compass setting, place the compass at point C and draw two more arcs that intersect the previous arcs above and below BC.

Draw a straight line connecting the two points where the arcs intersect. This line is the perpendicular bisector of BC, and it represents set S.
The locus is the perpendicular bisector of line segment BC.