plzz tell me how to construct 120 degree angle with the help of compass....

plzz do it fastly....

1. Draw a line segment AB.

2. With A as centre, draw an arc, intersecting the line segment AB at point O.

3. With O as centre and same radius draw an arc that cuts the previous arc at point C.

4. With C as centre and same radius, again draw an arc intersecting the previous arc at point D.

5. Join AD and extend it to P.

6. Hence, PAB is the required angle.

where AP and AB are the arms of the angle and A is the vertex of angle.