Which of the following statements are true for the 'Rise and Fall method' for calculating the reduced levels? i. It provides a check on the Reduced Levels of the intermediate locations ii. It is less accurate than the height of the instrument method iii. It is quicker and less tedious for large number of intermediate sights.
- AOnly (i)Correct
- B(i) and (ii)
- C(ii) and (iii)
- D(i) and (iii)
Solution
Concept
Rise and fall vs height of collimation
Step-by-step solution
1. The rise and fall method checks the RLs of all points, including intermediate ones (i true). 2. It is more accurate but more tedious than the height of instrument method (ii and iii false).
Explanation
The height of instrument method is quicker for many intermediate sights.
Why the other options are wrong
Options with (ii) or (iii) reverse the comparison.
Shortcut
Rise & fall: check on all RLs, more work.
Correct answer: A) Only (i)