Answer:
2096.34 ft
Explanation:
You are given the angle, (11 degrees), and the altitude (400 feet).
In this case, in terms of triangles you have the opposite side and want to find the hypotenuse, so you will be using Sine.
sin(11) =

x(sin(11) =
)
x(sin(11)) = 400
x(sin(11))/sin(11) = 400/sin(11)
x = 2096.3337226 ft