Q. Which of the following errors can be eliminated by taking mean of bot faceobservations ? (Solved)
1. error due to imperfect graduations
2. error due to eccentricity of verniers
3. error due to imperfect adjustment of plate levels
4. error due to line of collimation not being perpendicular to horizontal axis
- d. error due to line of collimation not being perpendicular to horizontal axis