Answer:
The distance of helicopter from the injured person is 542.82 feet 
Explanation:
Given as :
The height of the hovering helicopter above the ground = h = 450 feet
The angle of elevation from injured person to helicopter = Ф = 56°
Or, Let the distance of of helicopter from person = x feet
Now, From Triangle
∵ Sin Ф = 

∴ Sin 56° = 

Or, 0.8290 = 

Or , x = 

I.e x = 542.82 feet
So, The distance from injured person to helicopter = 542.82 feet
Hence The distance of helicopter from the injured person is 542.82 feet Answer