Q5. Construct with ruler and compasses, angles of following measures:
The steps of constructions are:
1. Draw a ray OA
2. Taking O as the centre and convenient radius, mark an arc, which intersects OA at P.
3. Taking P as the centre and same radius, cut previous arc at Q. Taking Q as the centre and the same radius cut the arc at S. Join OS. Thus, ∠AOS is the required angle of 120°.