Answer:
12,897.69 ft
Step-by-step explanation:
The cable is assumed to be the hypotenuse of a right triangle with side lengths 11520 ft and 5800 ft. Then the length of it (in feet) is ...
cable length = √(11520² +5800²) = √166,350,400 ≈ 12,897.69 . . . feet
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Comment on the question
A cable that long will have considerable sag, so even an answer rounded to the nearest 10 ft is probably in error by quite a bit.
