A camera with a focal length of $20 \mathrm{~cm}$ fitted in an aircraft is used for taking vertical aerial photographs of a terrain. The average elevation of the terrain is $1200 \mathrm{~m}$ 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 $1: 8000 ?$
(A) $2600 \mathrm{~m}$
(B) $2800 \mathrm{~m}$
(C) $3000 \mathrm{~m}$
(D) $3200 \mathrm{~m}$
A camera with a focal length of $20 \mathrm{~cm}$ fitted in an aircraft is used for taking vertical aerial photographs of a terrain. The average elevation of the terrain is $1200 \mathrm{~m}$ 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 $1: 8000 ?$
(A) $2600 \mathrm{~m}$
(B) $2800 \mathrm{~m}$
(C) $3000 \mathrm{~m}$
(D) $3200 \mathrm{~m}$