165 feet
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To find the distance from the helicopter to the shark, we need to consider the depth of the water.
The shark is 15 feet below the water's surface, and the helicopter is 150 feet above sea level.
Therefore, the total distance from the helicopter to the shark is the sum of these two distances:
- 15 feet + 150 feet = 165 feet
So, the shark is 165 feet away from the helicopter.