Pick up the correct statement from the following:
A. If the applied tension to the tape is more than the standard, the tension correction is positive
B. If the applied tension to the tape is less than the standard, the tension correction is negative
C. If the temperature during measurement is greater than the standard temperature, the temperature correction is positive
D. All the above
Answer: Option D
A. Base line of the left photograph of stereo pair
B. Base line of the right photograph of stereo pair
C. Sum of the base lines of stereo pair
D. Mean of the base lines of the stereo pair
A. Error due to refraction may not be completely eliminated by reciprocal levelling.
B. Tilting levels are commonly used for precision work.
C. The last reading of levelling is always a foresight.
D. All of the above statements are incorrect.