Surveying
If v, t and f/H are the ground speed of the aircraft, the shutter speed of the camera and the scale of the photograph respectively, then the amount of image displacement

i = t. H/v. f
i = v. t. (f/H)
i = v. t. H/f
i = v. f/t. H

ANSWER DOWNLOAD EXAMIANS APP

Surveying
Dumpy level is most suitable when

many readings are to be taken from a single setting of the instrument
the instrument is to be shifted frequently
fly levelling is being done over long distance
All of these

ANSWER DOWNLOAD EXAMIANS APP