Answer: The required difference is 255 m .
Step-by-step explanation: Since we have given that
Distance at which the aircraft is above the surface = 200 m
Distance at which the submarine is below the surface = 55 m
Above the surface is represented as positive number i.e. (+) 200 m
Below the surface is represented as negative number i.e. (-) 55 m
Hence, the required difference is 255 m .
(sorry if im wrong)
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