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A camera with a focal length of 20 cm fitted in an aircraft is used for taking vertical aerial photographs of a terrain. The average elevation of the terrain is 1200 m above mean sea level (MSL). What is the height above MSL at which an aircraft must fly in order to get the aerial photographs at a scale of 1:8000?

1. 2600 m
2. 2800 m
3. 3000 m
4. 3200 m

Correct answer: 2800 m

Solution

To achieve a scale of 1:8000, the height at which the aircraft flies must be calculated based on the focal length of the camera and the elevation of the terrain. The correct height of 2800 m ensures that the scale is maintained, allowing for accurate aerial photographs of the terrain.

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