Answer: Distance between dolphin and helicopter = 93.5 feet
Explanation:
Distance at which dolphin swimming below the ocean= (-) 18 feet
(it is represented as the negative number as it denotes the distance below the ocean)
Distance at which helicopter is above the ocean = (+) 75.5 feet
(it is represented as the positive number as it denotes the distance above the ocean)
Distance between dolphin and helicopter = 75.5 - (-18) feet
= 75.5 + 18 feet
= 93.5 feet
