Answer:
The length of the rope between the boat and the dock is of 30 feet.
Explanation:
Given:
tan(40) ≈ 0.839
Angle of depression = 40 (deg)
Distance between boat and the floor of the ocean = 25.17 feet
If we look into the diagram we can see that,they form 2 right angled triangle.
Where we can say that :
Distance between boat and dock = Rope's distance = Base of the triangle.
Let the length of the rope be 'x' feet.
Considering the dotted triangle:

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Length of the rope between the boat and the dock is 'x' = 30 feet.