Draw a figure from the given data.

Since pilot wants to take the plane up to 20000 ft over the next 50 miles,

BC = 10000 ft, and AB = 50 miles.

Convert 50 miles into feet  or 264000 ft.

Angle of elevation is measure of A.

Use tangent ratio to find .

                   (Substitute )

A equals to invese tan of .

Use a calculater.

The angle of elevation of pilot to take the plane up over 20000 ft is nearly .