Answer:
Arc AB with a chord AB, and Trace a Circular Sector.
Step-by-step explanation:
1. With a Compass, open it a certain opening with the needle in point F, and with a pencil mark it on line. This is B.
2. With a Compass needle in the right end of line (B) mark the A.
3. With a Compass needle in F, mark A.
4. With a Compass needle in F, trace arc AB
With this construction, we have an arc with F, the Focus, Radius FA=FB, and AB perpendicular to F.
5. You can proceed with a Ruler connecting the dots F to A, and F to B and we can have a Circular Sector.